Copyright © 1997, 1998, 1999 by the PHP Documentation Group
Copyright
This manual is © Copyright 1997, 1998, 1999 the PHP Documentation Group. The members of this group are listed on the front page of this manual.
This manual can be redistributed under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
Date: 1999-08-07
PHP is an HTML-embedded scripting language. Much of its syntax is borrowed from C, Java and Perl with a couple of unique PHP-specific features thrown in. The goal of the language is to allow web developers to write dynamically generated pages quickly.
This manual is written in SGML using the DocBook DTD, using DSSSL (Document Style and Semantics Specification Language) for formatting. The tools used for formatting HTML, TeX and RTF versions are Jade, written by James Clark and The Modular DocBook Stylesheets written by Norman Walsh. PHP's documentation framework was assembled by Stig Sæther Bakken.
PHP is a server-side HTML-embedded scripting language.
Simple answer, but what does that mean? An example:
Example 1-1. An introductory example <html> <head> <title>Example</title> </head> <body> <?php echo "Hi, I'm a PHP script!"; ?> </body> </html> |
Notice how this is different from a CGI script written in other languages like Perl or C -- instead of writing a program with lots of commands to output HTML, you write an HTML script with a some embedded code to do something (in this case, output some text). The PHP code is enclosed in special start and end tags that allow you to jump into and out of "PHP mode".
What distinguishes PHP from something like client-side Javascript is that the code is executed on the server. If you were to have a script similar to the above on your server, the client would receive the results of running that script, with no way of determining what the underlying code may be. You can even configure your web server to process all your HTML files with PHP, and then there's really no way that users can tell what you have up your sleeve.
At the most basic level, PHP can do anything any other CGI program can do, such as collect form data, generate dynamic page content, or send and receive cookies.
Perhaps the strongest and most significant feature in PHP is its support for a wide range of databases. Writing a database-enabled web page is incredibly simple. The following databases are currently supported:
Adabas D InterBase Solid dBase mSQL Sybase Empress MySQL Velocis FilePro Oracle Unix dbm Informix PostgreSQL
PHP also has support for talking to other services using protocols such as IMAP, SNMP, NNTP, POP3, or even HTTP. You can also open raw network sockets and interact using other protocols.
PHP was conceived sometime in the fall of 1994 by Rasmus Lerdorf. Early non-released versions were used on his home page to keep track of who was looking at his online resume. The first version used by others was available sometime in early 1995 and was known as the Personal Home Page Tools. It consisted of a very simplistic parser engine that only understood a few special macros and a number of utilities that were in common use on home pages back then. A guestbook, a counter and some other stuff. The parser was rewritten in mid-1995 and named PHP/FI Version 2. The FI came from another package Rasmus had written which interpreted html form data. He combined the Personal Home Page tools scripts with the Form Interpreter and added mSQL support and PHP/FI was born. PHP/FI grew at an amazing pace and people started contributing code to it.
It is hard to give any hard statistics, but it is estimated that by late 1996 PHP/FI was in use on at least 15,000 web sites around the world. By mid-1997 this number had grown to over 50,000. Mid-1997 also saw a change in the development of PHP. It changed from being Rasmus' own pet project that a handful of people had contributed to, to being a much more organized team effort. The parser was rewritten from scratch by Zeev Suraski and Andi Gutmans and this new parser formed the basis for PHP Version 3. A lot of the utility code from PHP/FI was ported over to PHP3 and a lot of it was completely rewritten.
Today (mid-1999) either PHP/FI or PHP3 ships with a number of commercial products such as C2's StrongHold web server and RedHat Linux and a conservative estimate based on an extrapolation from numbers provided by NetCraft would be that PHP is in use on over 150,000 sites around the world. To put that in perspective, that is more sites than run Netscape's flagship Enterprise server on the Internet.
Also as of this writing, work is underway on the next generation of PHP that will utilize the powerful Zend scripting engine to deliver higher performance, and will also support running under webservers other than Apache as a native server module.
The source code, and binary distributions for some platforms (including Windows), can be found at http://www.php.net/.
This section will guide you through the configuration and installation of PHP. Prerequisite knowledge and software:
Basic UNIX skills (being able to operate "make" and a C compiler)
An ANSI C compiler
A web server
1. gunzip apache_1.3.x.tar.gz 2. tar xvf apache_1.3.x.tar 3. gunzip php-3.0.x.tar.gz 4. tar xvf php-3.0.x.tar 5. cd apache_1.3.x 6. ./configure --prefix=/www 7. cd ../php-3.0.x 8. ./configure --with-mysql --with-apache=../apache_1.3.x --enable-track-vars 9. make 10. make install 11. cd ../apache_1.3.x 12. ./configure --prefix=/www --activate-module=src/modules/php3/libphp3.a 13. make 14. make install Instead of this step you may prefer to simply copy the httpd binary overtop of your existing binary. Make sure you shut down your server first though. 15. cd ../php-3.0.x 16. cp php3.ini-dist /usr/local/lib/php3.ini You can edit /usr/local/lib/php3.ini file to set PHP options. If you prefer this file in another location, use --with-config-file-path=/path in step 8. 17. Edit your httpd.conf or srm.conf file and add: AddType application/x-httpd-php3 .php3 You can choose any extension you wish here. .php3 is simply the one we suggest. 18. Use your normal procedure for starting the Apache server. (You must stop and restart the server, not just cause the server to reload by use a HUP or USR1 signal.)
There are two ways of configuring PHP.
Using the "setup" script that comes with PHP. This script asks you a series of questions (almost like the "install" script of PHP/FI 2.0) and runs "configure" in the end. To run this script, type ./setup.
This script will also create a file called "do-conf", this file will contain the options passed to configure. You can edit this file to change just a few options without having to re-run setup. Then type ./do-conf to run configure with the new options.
Running configure by hand. To see what options you have, type ./configure --help.
Details about some of the different configuration options are listed below.
To build PHP as an Apache module, answer "yes" to "Build as an Apache module?" (the --with-apache=DIR option to configure) and specify the Apache distribution base directory. If you have unpacked your Apache distribution in /usr/local/www/apache_1.2.4, this is your Apache distribution base directory. The default directory is /usr/local/etc/httpd.
To build PHP as an fhttpd module, answer "yes" to "Build as an fhttpd module?" (the --with-fhttpd=DIR option to configure) and specify the fhttpd source base directory. The default directory is /usr/local/src/fhttpd. If you are running fhttpd, building PHP as a module will give better performance, more control and remote execution capability.
The default is to build PHP as a CGI program. If you are running a web server PHP has module support for, you should generally go for that solution for performance reasons. However, the CGI version enables Apache users to run different PHP-enabled pages under different user-ids. Please make sure you read through the Security chapter if you are going to run PHP as a CGI.
PHP has native support for a number of databases (as well as ODBC):
--with-adabas=DIR
Compiles with Adabas D support. The parameter is the Adabas D install directory and defaults to /usr/local/adabasd.
--with-filepro
Enables the bundled read-only filePro support. No external libraries are required.
--with-msql=DIR
Enables mSQL support. The parameter to this option is the mSQL install directory and defaults to /usr/local/Hughes. This is the default directory of the mSQL 2.0 distribution. configure automatically detects which mSQL version you are running and PHP supports both 1.0 and 2.0, but if you compile PHP with mSQL 1.0, you can only access mSQL 1.0 databases, and vice-versa.
See also mSQL Configuration Directives in the configuration file.
--with-mysql=DIR
Enables MySQL support. The parameter to this option is the MySQL install directory and defaults to /usr/local. This is the default installation directory of the MySQL distribution.
See also MySQL Configuration Directives in the configuration file.
--with-iodbc=DIR
Includes iODBC support. This feature was first developed for iODBC Driver Manager, a freely redistributable ODBC driver manager which runs under many flavors of UNIX. The parameter to this option is the iODBC installation directory and defaults to /usr/local.
--with-openlink=DIR
Includes OpenLink ODBC support. The parameter to this option is the OpenLink ODBC installation directory and defaults to /usr/local/openlink.
--with-oracle=DIR
Includes Oracle support. Has been tested and should be working at least with Oracle versions 7.0 through 7.3. The parameter is the ORACLE_HOME directory. You do not have to specify this parameter if your Oracle environment has been set up.
--with-pgsql=DIR
Includes PostgreSQL support. The parameter is the PostgreSQL base install directory and defaults to /usr/local/pgsql.
See also Postgres Configuration Directives in the configuration file.
--with-solid=DIR
Includes Solid support. The parameter is the Solid install directory and defaults to /usr/local/solid.
--with-sybase=DIR
Includes Sybase support. The parameter is the Sybase install directory and defaults to /home/sybase.
See also Sybase Configuration Directives in the configuration file.
--with-sybase-ct=DIR
Includes Sybase-CT support. The parameter is the Sybase-CT install directory and defaults to /home/sybase.
See also Sybase-CT Configuration Directives in the configuration file.
--with-velocis=DIR
Includes Velocis support. The parameter is the Velocis install directory and defaults to /usr/local/velocis.
--with-custom-odbc=DIR
Includes support for an arbitrary custom ODBC library. The parameter is the base directory and defaults to /usr/local.
This option implies that you have defined CUSTOM_ODBC_LIBS when you run the configure script. You also must have a valid odbc.h header somewhere in your include path. If you don't have one, create it and include your specific header from there. Your header may also require some extra definitions, particularly when it is multiplatform. Define them in CFLAGS.
For example, you can use Sybase SQL Anywhere on QNX as following: CFLAGS=-DODBC_QNX LDFLAGS=-lunix CUSTOM_ODBC_LIBS="-ldblib -lodbc" ./configure --with-custom-odbc=/usr/lib/sqlany50
--disable-unified-odbc
Disables the Unified ODBC module, which is a common interface to all the databases with ODBC-based interfaces, such as Solid and Adabas D. It also works for normal ODBC libraries. Has been tested with iODBC, Solid, Adabas D and Sybase SQL Anywhere. Requires that one (and only one) of these modules or the Velocis module is enabled, or a custom ODBC library specified. This option is only applicable if one of the following options is used: --with-iodbc, --with-solid, --with-adabas, --with-velocis, or --with-custom-odbc,
See also Unified ODBC Configuration Directives in the configuration file.
--with-mcrypt
Include support for the mcrypt library. See the mcrypt documentation for more information. If you use the optional DIR argument, PHP will look for mcrypt.h in DIR/include.
--enable-sysvsem
Include support for Sys V semaphores (supported by most Unix derivates). See the Semaphore and Shared Memory documentation for more information.
--enable-sysvshm
Include support for Sys V shared memory (supported by most Unix derivates). See the Semaphore and Shared Memory documentation for more information.
--with-xml
Include support for a non-validating XML parser using James Clark's expat library. See the XML function reference for details.
--enable-maintainer-mode
Turns on extra dependencies and compiler warnings used by some of the PHP developers.
--with-system-regex
Uses the system's regular expression library rather than the bundled one. If you are building PHP as a server module, you must use the same library when building PHP as when linking the server. Enable this if the system's library provides special features you need. It is recommended that you use the bundled library if possible.
--with-config-file-path=DIR
The path used to look for the configuration file when PHP starts up.
--with-exec-dir=DIR
Only allow running of executables in DIR when in safe mode. Defaults to /usr/local/bin. This option only sets the default, it may be changed with the safe_mode_exec_dir directive in the configuration file later.
--enable-debug
Enables extra debug information. This makes it possible to gather more detailed information when there are problems with PHP. (Note that this doesn't have anything to do with debugging facilities or information available to PHP scripts.)
--enable-safe-mode
Enables "safe mode" by default. This imposes several restrictions on what PHP can do, such as opening only files within the document root. Read the Security chapter for more more information. CGI users should always enable secure mode. This option only sets the default, it may be enabled or disabled with the safe_mode directive in the configuration file later.
--enable-track-vars
Makes PHP keep track of where GET/POST/cookie variables come from in the arrays HTTP_GET_VARS, HTTP_POST_VARS and HTTP_COOKIE_VARS. This option only sets the default, it may be enabled or disabled with the track_vars directive in the configuration file later.
--enable-magic-quotes
Enable magic quotes by default. This option only sets the default, it may be enabled or disabled with the magic_quotes_runtime directive in the configuration file later. See also the magic_quotes_gpc and the magic_quotes_sybase directives.
--enable-debugger
Enables the internal PHP debugger support. This feature is still in an experimental state. See also the Debugger Configuration directives in the configuration file.
--enable-discard-path
If this is enabled, the PHP CGI binary can safely be placed outside of the web tree and people will not be able to circumvent .htaccess security. Read the section in the security chapter about this option.
--enable-bcmath
Enables bc style arbitrary precision math functions. See also the bcmath.scale option in the configuration file.
--enable-force-cgi-redirect
Enable the security check for internal server redirects. You should use this if you are running the CGI version with Apache.
When using PHP as a CGI binary, PHP by default always first checks that it is used by redirection (for example under Apache, by using Action directives). This makes sure that the PHP binary cannot be used to bypass standard web server authentication procedures by calling it directly, like http://my.host/cgi-bin/php/secret/doc.html. This example accesses http://my.host/secret/doc.html but does not honour any security settings enforced by httpd for directory /secret.
Not enabling option disables the check and enables bypassing httpd security and authentication settings. Do this only if your server software is unable to indicate that a safe redirection was done and all your files under your document root and user directories may be accessed by anyone.
Read the section in the security chapter about this option.
--disable-short-tags
Disables the short form <? ?> PHP tags. You must disable the short form if you want to use PHP with XML. With short tags disabled, the only PHP code tag is <?php ?>. This option only sets the default, it may be enabled or disabled with the short_open_tag directive in the configuration file later.
--enable-url-includes
Makes it possible to run code on other HTTP or FTP servers directly from PHP with include(). See also the include_path option in the configuration file.
To make the PHP installation look for header or library files in different directories, modify the CPPFLAGS and LDFLAGS environment variables, respectively. If you are using a sensible shell, you should be able to do LDFLAGS=-L/my/lib/dir CPPFLAGS=-I/my/include/dir ./configure
When PHP is configured, you are ready to build the CGI executable or the PHP library. The command make should take care of this. If it fails and you can't figure out why, see the Problems section.
If you have built PHP as a CGI program, you may test your build by typing make test. It is always a good idea to test your build. This way you may catch a problem with PHP on your platform early instead of having to struggle with it later.
If you have built PHP as a CGI program, you may benchmark your build by typing make bench. Note that if safe mode is on by default, the benchmark may not be able to finish if it takes longer then the 30 seconds allowed. This is because the set_time_limit() can not be used in safe mode. Use the max_execution_time configuration setting to control this time for you own scripts. make bench ignores the configuration file.
This install guide will help you install and configure PHP on your Windows 9x/NT webservers. This guide was compiled by Bob Silva. The latest revision can be found at http://www.umesd.k12.or.us/php/win32install.html.
This guide provides installation support for:
Personal Web Server (Newest version recommended)
Internet Information Server 3 or 4
Apache 1.3.x
Omni HTTPd 2.0b1
The following steps should be performed on all installations before the server specific instructions.
Extract the distribution file to a directory of your choice. "C:\PHP3\" is a good start.
Copy the file, 'php3-dist.ini' to your '%WINDOWS%' directory and rename it to 'php3.ini'. Your '%WINDOWS%' directory is typically:
c:\windows for Windows 95/98 |
c:\winnt or c:\winnt40 for NT servers |
Edit your 'php3.ini' file:
You will need to change the 'extension_dir' setting to point to your php-install-dir, or where you have placed your 'php3_*.dll' files. ex: c:\php3
If you are using Omni Httpd, do not follow the next step. Set the 'doc_root' to point to your webservers document_root. ex: c:\apache\htdocs or c:\webroot
Choose which modules you would like to load when PHP starts. You can uncomment the: 'extension=php3_*.dll' lines to load these modules. Some modules require you to have additional libraries installed on your system for the module to work correctly. The PHP FAQ has more information on where to get supporting libraries. You can also load a module dynamically in your script using: dl("php_*.dll");
On PWS and IIS, you can set the browscap.ini to point to: 'c:\windows\system\inetsrv\browscap.ini' on Windows 95/98 and 'c:\winnt\system32\inetsrv\browscap.ini' on NT Server. Additional information on using the browscap functionality in PHP can be found at this mirror, select the "source" button to see it in action.
The DLLs for PHP extensions are prefixed with 'php3_'. This prevents confusion between PHP extensions and their supporting libraries.
The recommended method for configuring these servers is to use the INF file included with the distribution (php_iis_reg.inf). You may want to edit this file and make sure the extensions and PHP install directories match your configuration. Or you can follow the steps below to do it manually.
WARNING: These steps involve working directly with the windows registry. One error here can leave your system in an unstable state. We highly recommend that you back up your registry first. The PHP Development team will not be held responsible if you damage your registry.
Run Regedit.
Navigate to: HKEY_LOCAL_MACHINE /System /CurrentControlSet /Services /W3Svc /Parameters /ScriptMap.
On the edit menu select: New->String Value.
Type in the extension you wish to use for your php scripts. ex: .php3
Double click on the new string value and enter the path to php.exe in the value data field. ex: c:\php3\php.exe %s %s. The '%s %s' is VERY important, PHP will not work properly without it.
Repeat these steps for each extension you wish to associate with PHP scripts.
Now navigate to: HKEY_CLASSES_ROOT
On the edit menu select: New->Key.
Name the key to the extension you setup in the previous section. ex: .php3
Highlight the new key and in the right side pane, double click the "default value" and enter phpfile.
Repeat the last step for each extension you set up in the previous section.
Now create another New->Key under HKEY_CLASSES_ROOT and name it phpfile.
Highlight the new key phpfile and in the right side pane, double click the "default value" and enter PHP Script.
Right click on the phpfile key and select New->Key, name it Shell.
Right click on the Shell key and select New->Key, name it open.
Right click on the open key and select New->Key, name it command.
Highlight the new key command and in the right side pane, double click the "default value" and enter the path to php.exe. ex: c:\php3\php.exe -q %1. (don't forget the %1).
Exit Regedit.
PWS and IIS 3 users now have a fully operational system. IIS 3 users can use a nifty tool from Steven Genusa to configure their script maps.
To install PHP on an NT Server running IIS 4, follow these instructions:
In Internet Service Manager (MMC), select the Web site or the starting point directory of an application.
Open the directory's property sheets (by right clicking and selecting properties), and then click the Home Directory, Virtual Directory, or Directory tab.
Click the Configuration button, and then click the App Mappings tab.
Click Add, and in the Executable box, type: c:\path-to-php-dir\php.exe %s %s. You MUST have the %s %s on the end, PHP will not function properly if you fail to do this.
In the Extension box, type the file name extension you want associated with PHP scripts. (You must repeat step 5 and 6 for each extension you want accociated with PHP scripts. (.php3 and .phtml are common)
Set up the appropriate security. (This is done in Internet Service Manager), and if your NT Server uses NTFS file system, add execute rights for I_USR_ to the directory that contains php.exe.
You must edit your srm.conf or httpd.conf to configure Apache to work with the PHP CGI binary.
Although there can be a few variations of configuring PHP under Apache, this one is simple enough to be used by the newcomer. Please consult the Apache Docs for further configuration directives.
ScriptAlias /php3/ "c:/path-to-php-dir/"
AddType application/x-httpd-php3 .php3
AddType application/x-httpd-php3 .phtml
Action application/x-httpd-php3 "/php3/php.exe"
To use the source code highlighting feature, simply create a PHP script file and stick this code in: <?php show_source ("original_php_script.php3"); ?>. Substitute original_php_script.php3 with the name of the file you wish to show the source of. (this is only one way of doing it). Note: On Win-Apache all back slashes in a path statement such as: "c:\directory\file.ext", must be converted to forward slashes.
This has got to be the easiest config there is:
Step 1: Install Omni server |
Step 2: Right click on the blue OmniHTTPd icon in the system tray and select Properties |
Step 3: Click on Web Server Global Settings |
Step 4: On the 'External' tab, enter: virtual = .php3 | actual = c:\path-to-php-dir\php.exe |
Step 5: On the Mime tab, enter: virtual = wwwserver/stdcgi | actual = .php3 |
Step 6: Click OK |
Repeat steps 2 - 6 for each extension you want to associate with PHP.
Table 2-1. PHP Modules
php3_calendar.dll | Calendar conversion functions |
php3_crypt.dll | Crypt functions |
php3_dbase.dll | DBase functions |
php3_dbm.dll | GDBM emulation via Berkely DB2 library |
php3_filepro.dll | READ ONLY access to filepro databases |
php3_gd.dll | GD Library functions for gif manipulation |
php3_hyperwave.dll | HyperWave functions |
php3_imap4r2.dll | IMAP 4 functions |
php3_ldap.dll | LDAP functions |
php3_msql1.dll | mSQL 1 client |
php3_msql2.dll | mSQL 2 client |
php3_mssql.dll | MSSQL client (requires MSSQL DB-Libraries |
php3_mysql.dll | MySQL functions |
php3_nsmail.dll | Netscape mail functions |
php3_oci73.dll | Oracle functions |
php3_snmp.dll | SNMP get and walk functions (NT only!) |
php3_zlib.dll | ZLib functions |
Some problems are more common than others. The most common ones are listed in the PHP FAQ, found at http://www.php.net/FAQ.php3
If you think you have found a bug in PHP, please report it. The PHP developers probably don't know about it, and unless you report it, chances are it won't be fixed. You can report bugs using the bug-tracking system at http://www.php.net/bugs.php3.
If you are still stuck, someone on the PHP mailing list may be able to help you. You should check out the archive first, in case someone already answered someone else who had the same problem as you. The archives are available from the support page on http://www.php.net/. To subscribe to the PHP mailing list, send an empty mail to php3-subscribe@lists.php.net. The mailing list address is php3@lists.php.net.
If you want to get help on the mailing list, please try to be precise and give the necessary details about your environment (which operating system, what PHP version, what web server, if you are running PHP as CGI or a server module, etc.), and preferably enough code to make others able to reproduce and test your problem.
The configuration file (called php3.ini in PHP 3.0, and simply php.ini as of PHP 4.0) is read when PHP starts up. For the server module versions of PHP, this happens only once when the web server is started. For the CGI version, it happens on every invocation.
When using PHP as an Apache module, you can also change the configuration settings using directives in Apache configuration files and .htaccess files.
With PHP 3.0, there are Apache directives that correspond to each configuration setting in the php3.ini name, except the name is prefixed by "php3_".
With PHP 4.0, there are just a few Apache directives that allow you to change the PHP configuration settings.
This sets the value of the specified variable.
This is used to set a Boolean configuration option.
This sets the value of the specified variable. "Admin" configuration settings can only be set from within the main Apache configuration files, and not from .htaccess files.
This is used to set a Boolean configuration option.
You can view the settings of the configuration values in the output of phpinfo(). You can also access the values of individial configuration settings using get_cfg_var().
Specifies the name of a file that is automatically parsed after the main file. The file is included as if it was called with the include() function, so include_path is used.
The special value none disables auto-appending.
Note: If the script is terminated with exit(), auto-append will not occur.
Specifies the name of a file that is automatically parsed before the main file. The file is included as if it was called with the include() function, so include_path is used.
The special value none disables auto-prepending.
This determines whether errors should be printed to the screen as part of the HTML output or not.
PHP's "root directory" on the server. Only used if non-empty. If PHP is configured with safe mode, no files outside this directory are served.
This directive is really only useful in the Apache module version of PHP. It is used by sites that would like to turn PHP parsing on and off on a per-directory or per-virtual server basis. By putting php3_engine off in the appropriate places in the httpd.conf file, PHP can be enabled or disabled.
Name of file where script errors should be logged. If the special value syslog is used, the errors are sent to the system logger instead. On UNIX, this means syslog(3) and on Windows NT it means the event log. The system logger is not supported on Windows 95.
Set the error reporting level. The parameter is an integer representing a bit field. Add the values of the error reporting levels you want.
Table 3-1. Error Reporting Levels
bit value | enabled reporting |
---|---|
1 | normal errors |
2 | normal warnings |
4 | parser errors |
8 | non-critical style-related warnings |
Limit the files that can be opened by PHP to the specified directory-tree.
When a script tries to open a file with, for example, fopen or gzopen, the location of the file is checked. When the file is outside the specified directory-tree, PHP will refuse to open it. All symbolic links are resolved, so it's not possible to avoid this restriction with a symlink.
The special value . indicates that the directory in which the script is stored will be used as base-directory.
Under Windows, separate the directories with a semicolon. On all other systems, separate the directories with a colon. As an Apache module, open_basedir paths from parent directories are now automatically inherited.
Note: Support for multiple directories was added in 3.0.7.
The default is to allow all files to be opened.
Set the order of GET/POST/COOKIE variable parsing. The default setting of this directive is "GPC". Setting this to "GP", for example, will cause PHP to completely ignore cookies and to overwrite any GET method variables with POST-method variables of the same name.
Off by default. If changed to On scripts will run to completion even if the remote client disconnects in the middle. See also ignore_user_abort().
Specifies a list of directories where the require(), include() and fopen_with_path() functions look for files. The format is like the system's PATH environment variable: a list of directories separated with a colon in UNIX or semicolon in Windows.
Example 3-1. UNIX include_path include_path=.:/home/httpd/php-lib |
Example 3-2. Windows include_path include_path=".;c:\www\phplib" |
Tells whether script error messages should be logged to the server's error log. This option is thus server-specific.
Sets the magic_quotes state for GPC (Get/Post/Cookie) operations. When magic_quotes are on, all ' (single-quote), " (double quote), \ (backslash) and NUL's are escaped with a backslash automatically. If magic_quotes_sybase is also on, a single-quote is escaped with a single-quote instead of a backslash.
If magic_quotes_runtime is enabled, most functions that return data from any sort of external source including databases and text files will have quotes escaped with a backslash. If magic_quotes_sybase is also on, a single-quote is escaped with a single-quote instead of a backslash.
If magic_quotes_sybase is also on, a single-quote is escaped with a single-quote instead of a backslash if magic_quotes_gpc or magic_quotes_runtime is enabled.
This sets the maximum time in seconds a script is allowed to take before it is terminated by the parser. This helps prevent poorly written scripts from tieing up the server.
This sets the maximum amount of memory in bytes that a script is allowed to allocate. This helps prevent poorly written scripts for eating up all available memory on a server.
Tells whether the short form (<? ?>of PHP's open tag should be allowed. If you want to use PHP in combination with XML, you have to disable this option. If disabled, you must use the long form of the open tag (<?php ?>).
If enabled, the last error message will always be present in the global variable $php_errormsg.
If enabled, GET, POST and cookie input can be found in the global associative arrays $HTTP_GET_VARS, $HTTP_POST_VARS and $HTTP_COOKIE_VARS, respectively.
The temporary directory used for storing files when doing file upload. Must be writable by whatever user PHP is running as.
The base name of the directory used on a user's home directory for PHP files, for example public_html.
If enabled, this option makes PHP output a warning when the plus (+) operator is used on strings. This is to make it easier to find scripts that need to be rewritten to using the string concatenator instead (.).
DNS name or IP address of the SMTP server PHP under Windows should use for mail sent with the mail() function.
Which "From:" mail address should be used in mail sent from PHP under Windows.
Where the sendmail program can be found, usually /usr/sbin/sendmail or /usr/lib/sendmail configure does an honest attempt of locating this one for you and set a default, but if it fails, you can set it here.
Systems not using sendmail should set this directive to the sendmail wrapper/replacement their mail system offers, if any. For example, Qmail users can normally set it to /var/qmail/bin/sendmail.
Whether to enable PHP's safe mode. Read the Security chapter for more more information.
If PHP is used in safe mode, system() and the other functions executing system programs refuse to start programs that are not in this directory.
DNS name or IP address of host used by the debugger.
Port number used by the debugger.
Whether the debugger is enabled.
This directive is really only useful in the Apache module version of PHP. You can turn dynamic loading of PHP extensions with dl() on and off per virtual server or per directory.
The main reason for turning dynamic loading off is security. With dynamic loading, it's possible to ignore all the safe_mode and open_basedir restrictions.
The default is to allow dynamic loading, except when using safe-mode. In safe-mode, it's always imposible to use dl().
In what directory PHP should look for dynamically loadable extensions.
Which dynamically loadable extensions to load when PHP starts up.
Whether to allow persistent MySQL connections.
The maximum number of persistent MySQL connections per process.
The maximum number of MySQL connections per process, including persistent connections.
Whether to allow persistent mSQL connections.
The maximum number of persistent mSQL connections per process.
The maximum number of mSQL connections per process, including persistent connections.
Whether to allow persistent Postgres connections.
The maximum number of persistent Postgres connections per process.
The maximum number of Postgres connections per process, including persistent connections.
Whether to allow persistent Sybase connections.
The maximum number of persistent Sybase connections per process.
The maximum number of Sybase connections per process, including persistent connections.
Whether to allow persistent Sybase-CT connections. The default is on.
The maximum number of persistent Sybase-CT connections per process. The default is -1 meaning unlimited.
The maximum number of Sybase-CT connections per process, including persistent connections. The default is -1 meaning unlimited.
Server messages with severity greater than or equal to sybct.min_server_severity will be reported as warnings. This value can also be set from a script by calling sybase_min_server_severity(). The default is 10 which reports errors of information severity or greater.
Client library messages with severity greater than or equal to sybct.min_client_severity will be reported as warnings. This value can also be set from a script by calling sybase_min_client_severity(). The default is 10 which effectively disables reporting.
The maximum time in seconds to wait for a connection attempt to succeed before returning failure. Note that if max_execution_time has been exceeded when a connection attempt times out, your script will be terminated before it can take action on failure. The default is one minute.
The maximum time in seconds to wait for a select_db or query operation to succeed before returning failure. Note that if max_execution_time has been exceeded when am operation times out, your script will be terminated before it can take action on failure. The default is no limit.
The name of the host you claim to be connecting from, for display by sp_who. The default is none.
Whether to allow persistent Informix connections.
The maximum number of persistent Informix connections per process.
The maximum number of Informix connections per process, including persistent connections.
The default host to connect to when no host is specified in ifx_connect() or ifx_pconnect().
The default user id to use when none is specified in ifx_connect() or ifx_pconnect().
The default password to use when none is specified in ifx_connect() or ifx_pconnect().
Set to true if you want to return blob columns in a file, false if you want them in memory. You can override the setting at runtime with ifx_blobinfile_mode().
Set to true if you want to return TEXT columns as normal strings in select statements, false if you want to use blob id parameters. You can override the setting at runtime with ifx_textasvarchar().
Set to true if you want to return BYTE columns as normal strings in select queries, false if you want to use blob id parameters. You can override the setting at runtime with ifx_textasvarchar().
Set to true if you want to trim trailing spaces from CHAR columns when fetching them.
Set to true if you want to return NULL columns as the literal string "NULL", false if you want them returned as the empty string "". You can override this setting at runtime with ifx_nullformat().
Number of decimal digits for all bcmath functions.
ODBC data source to use if none is specified in odbc_connect() or odbc_pconnect().
User name to use if none is specified in odbc_connect() or odbc_pconnect().
Password to use if none is specified in odbc_connect() or odbc_pconnect().
Whether to allow persistent ODBC connections.
The maximum number of persistent ODBC connections per process.
The maximum number of ODBC connections per process, including persistent connections.
PHP is a powerful language and the interpreter, whether included in a web server as a module or executed as a separate CGI binary, is able to access files, execute commands and open network connections on the server. These properties make anything run on a web server insecure by default. PHP is designed specifically to be a more secure language for writing CGI programs than Perl or C, and with correct selection of compile-time and runtime configuration options it gives you exactly the combination of freedom and security you need.
As there are many different ways of utilizing PHP, there are many configuration options controlling its behaviour. A large selection of options guarantees you can use PHP for a lot of purposes, but it also means there are combinations of these options and server configurations that result in an insecure setup. This chapter explains the different configuration option combinations and the situations they can be safely used.
Using PHP as a CGI binary is an option for setups that for some reason do not wish to integrate PHP as a module into server software (like Apache), or will use PHP with different kinds of CGI wrappers to create safe chroot and setuid environments for scripts. This setup usually involves installing executable PHP binary to the web server cgi-bin directory. CERT advisory CA-96.11 recommends agains placing any interpreters into cgi-bin. Even if the PHP binary can be used as a standalone interpreter, PHP is designed to prevent the attacks this setup makes possible:
Accessing system files: http://my.host/cgi-bin/php?/etc/passwd
The query information in an url after the question mark (?) is passed as command line arguments to the interpreter by the CGI interface. Usually interpreters open and execute the file specified as the first argument on the command line.
When invoked as a CGI binary, PHP refuses to interpret the command line arguments.
Accessing any web document on server: http://my.host/cgi-bin/php/secret/doc.html
The path information part of the url after the PHP binary name, /secret/doc.html is conventionally used to specify the name of the file to be opened and interpreted by the CGI program. Usually some web server configuration directives (Apache: Action) are used to redirect requests to documents like http://my.host/secret/script.php3 to the PHP interpreter. With this setup, the web server first checks the access permissions to the directory /secret, and after that creates the redirected request http://my.host/cgi-bin/php/secret/script.php3. Unfortunately, if the request is originally given in this form, no access checks are made by web server for file /secret/script.php3, but only for the /cgi-bin/php file. This way any user able to access /cgi-bin/php is able to access any protected document on the web server.
In PHP, compile-time configuration option --enable-force-cgi-redirect and runtime configuration directives doc_root and user_dir can be used to prevent this attack, if the server document tree has any directories with access restrictions. See below for full explanation of different combinations.
If your server does not have any content that is not restricted by password or ip based access control, there is no need for these configuration options. If your web server does not allow you to do redirects, or the server does not have a way to communicate with the PHP binary that the request is a safely redirected request, you can specify the option --disable-force-cgi-redirect to the configure script. You still have to make sure your PHP scripts do not rely on one or another way of calling the script, neither by directly http://my.host/cgi-bin/php/dir/script.php3 nor by redirection http://my.host/dir/script.php3.
Redirection can be configured in Apache by using AddHandler and Action directives (see below).
This compile-time option prevents anyone from calling PHP directly with a url like http://my.host/cgi-bin/php/secretdir/script.php3. Instead, PHP will only parse in this mode if it has gone through a web server redirect rule.
Usually the redirection in the Apache configuration is done with the following directives:
Action php3-script /cgi-bin/php AddHandler php3-script .php3
This option has only been tested with the Apache web server, and relies on Apache to set the non-standard CGI environment variable REDIRECT_STATUS on redirected requests. If your web server does not support any way of telling if the request is direct or redirected, you cannot use this option and you must use one of the other ways of running the CGI version documented here.
To include active content, like scripts and executables, in the web server document directories is sometimes consider an insecure practice. If for some configuration mistake the scripts are not executed but displayed as usual HTML documents, this may result in leakage of intellectual property or security information like passwords. Therefore many sysadmins will prefer setting up another directory structure for scripts that is only accessible through the PHP CGI, and therefore always interpreted and not displayed as such.
Also if the method for making sure the requests are not redirected, as described in the previous section, is not available, it is necessary to set up a script doc_root that is different from web document root.
You can set the PHP script document root by the configuration directive doc_root in the configuration file, or you can set the environment variable PHP_DOCUMENT_ROOT. If it is set, the CGI version of PHP will always construct the file name to open with this doc_root and the path information in the request, so you can be sure no script is executed outside this directory (except for user_dir below).
Another option usable here is user_dir. When user_dir is unset, only thing controlling the opened file name is doc_root. Opening an url like http://my.host/~user/doc.php3 does not result in opening a file under users home directory, but a file called ~user/doc.php3 under doc_root (yes, a directory name starting with a tilde [~]).
If user_dir is set to for example public_php, a request like http://my.host/~user/doc.php3 will open a file called doc.php3 under the directory named public_php under the home directory of the user. If the home of the user is /home/user, the file executed is /home/user/public_php/doc.php3.
user_dir expansion happens regardless of the doc_root setting, so you can control the document root and user directory access separately.
A very secure option is to put the PHP parser binary somewhere outside of the web tree of files. In /usr/local/bin, for example. The only real downside to this option is that you will now have to put a line similar to:
#!/usr/local/bin/php
To get PHP to handle PATH_INFO and PATH_TRANSLATED information correctly with this setup, the php parser should be compiled with the --enable-discard-path configure option.
When PHP is used as an Apache module it inherits Apache's user permissions (typically those of the "nobody" user).
There are four ways of escaping from HTML and entering "PHP code mode":
Example 5-1. Ways of escaping from HTML 1. <? echo ("this is the simplest, an SGML processing instruction\n"); ?> 2. <?php echo("if you want to serve XML documents, do like this\n"); ?> 3. <script language="php"> echo ("some editors (like FrontPage) don't like processing instructions"); </script> 4. <% echo ("You may optionally use ASP-style tags"); %> <%= $variable; # This is a shortcut for "<%echo .." %> |
The first way is only available if short tags have been enabled (either by calling short_tags(), they are configured on using the short_tags run-time configuration setting, or they are enabled using the --enable-short-tags compile-time configuration setting.
The fourth way is only available if ASP-style tags have been enabled using either the asp_tags configuration setting or the --enable-asp-tags compile-time configuration setting.
Note: Support for ASP-style tags was added in 3.0.4.
The closing "bracket" for the block will include the immediately trailing newline if one is present.
Instructions are separated the same as in C or perl - terminate each statement with a semicolon.
The closing tag (?>) also implies the end of the statement, so the following are equivalent:
<?php echo "This is a test"; ?> <?php echo "This is a test" ?>
PHP supports 'C', 'C++' and Unix shell-style comments. For example:
<?php echo "This is a test"; // This is a one-line c++ style comment /* This is a multi line comment yet another line of comment */ echo "This is yet another test"; echo "One Final Test"; # This is shell-style style comment ?>
The "one-line" comment styles actually only comment to the end of the line or the current block of PHP code, whichever comes first.
<h1>This is an <?# echo "simple";?> example.</h1> <p>The header above will say 'This is an example'.
You should be careful not to nest 'C' style comments, which can happen when commenting out large blocks.
<?php /* echo "This is a test"; /* This comment will cause a problem */ */ ?>
PHP supports the following types:
The type of a variable is usually not set by the programmer; rather, it is decided at runtime by PHP depending on the context in which that variable is used.
If you would like to force a variable to be converted to a certain type, you may either cast the variable or use the settype() function on it.
Note that a variable may behave in different manners in certain situations, depending on what type it is a the time. For more information, see the section on Type Juggling.
Integers can be specified using any of the following syntaxes:
$a = 1234; # decimal number $a = -123; # a negative number $a = 0123; # octal number (equivalent to 83 decimal) $a = 0x12; # hexadecimal number (equivalent to 18 decimal)
Floating point numbers ("doubles") can be specified using any of the following syntaxes:
$a = 1.234; $a = 1.2e3;
Strings can be specified using one of two sets of delimiters.
If the string is enclosed in double-quotes ("), variables within the string will be expanded (subject to some parsing limitations). As in C and Perl, the backslash ("\") character can be used in specifying special characters:
Table 6-1. Escaped characters
sequence | meaning |
---|---|
\n | newline |
\r | carriage |
\t | horizontal tab |
\\ | backslash |
\$ | dollar sign |
\" | double-quote |
You can escape any other character, but a warning will be issued at the highest warning level.
The second way to delimit a string uses the single-quote ("'") character, which does not do any variable expansion or backslash processing (except for "\\" and "\'" so you can insert backslashes and single-quotes in a singly-quoted string).
When a string is evaluated as a numeric value, the resulting value and type are determined as follows.
The string will evaluate as a double if it contains any of the characters '.', 'e', or 'E'. Otherwise, it will evaluate as an integer.
The value is given by the initial portion of the string. If the string starts with valid numeric data, this will be the value used. Otherwise, the value will be 0 (zero). Valid numeric data is an optional sign, followed by one or more digits (optionally containing a decimal point), followed by an optional exponent. The exponent is an 'e' or 'E' followed by one or more digits.
When the first expression is a string, the type of the variable will depend on the second expression.
$foo = 1 + "10.5"; // $foo is double (11.5) $foo = 1 + "-1.3e3"; // $foo is double (-1299) $foo = 1 + "bob-1.3e3"; // $foo is integer (1) $foo = 1 + "bob3"; // $foo is integer (1) $foo = 1 + "10 Small Pigs"; // $foo is integer (11) $foo = 1 + "10 Little Piggies"; // $foo is integer (11) $foo = "10.0 pigs " + 1; // $foo is integer (11) $foo = "10.0 pigs " + 1.0; // $foo is double (11)
For more information on this conversion, see the Unix manual page for strtod(3).
Arrays actually act like both hash tables (associative arrays) and indexed arrays (vectors).
PHP supports both scalar and associative arrays. In fact, there is no difference between the two. You can create an array using the list() or array() functions, or you can explicitly set each array element value.
$a[0] = "abc"; $a[1] = "def"; $b["foo"] = 13;
You can also create an array by simply adding values to the array.
$a[] = "hello"; // $a[2] == "hello" $a[] = "world"; // $a[3] == "world"
Arrays may be sorted using the asort(), arsort(), ksort(), rsort(), sort(), uasort(), usort(), and uksort() functions depending on the type of sort you want.
You can count the number of items in an array using the count() function.
You can traverse an array using next() and prev() functions. Another common way to traverse an array is to use the each() function.
Multi-dimensional arrays are actually pretty simple. For each dimension of the array, you add another [key] value to the end:
$a[1] = $f; # one dimensional examples $a["foo"] = $f; $a[1][0] = $f; # two dimensional $a["foo"][2] = $f; # (you can mix numeric and associative indices) $a[3]["bar"] = $f; # (you can mix numeric and associative indices) $a["foo"][4]["bar"][0] = $f; # four dimensional!
You can "fill up" multi-dimensional arrays in many ways, but the trickiest one to understand is how to use the array() command for associative arrays. These two snippets of code fill up the one-dimensional array in the same way:
# Example 1: $a["color"] = "red"; $a["taste"] = "sweet"; $a["shape"] = "round"; $a["name"] = "apple"; $a[3] = 4; # Example 2: $a = array( "color" => "red", "taste" => "sweet", "shape" => "round", "name" => "apple", 3 => 4 );
The array() function can be nested for multi-dimensional arrays:
<? $a = array( "apple" => array( "color" => "red", "taste" => "sweet", "shape" => "round" ), "orange" => array( "color" => "orange", "taste" => "sweet", "shape" => "round" ), "banana" => array( "color" => "yellow", "taste" => "paste-y", "shape" => "banana-shaped" ) ); echo $a["apple"]["taste"]; # will output "sweet" ?>
To initialize an object, you use the new statement to instantiate the object to a variable.
class foo { function do_foo () { echo "Doing foo."; } } $bar = new foo; $bar -> do_foo ();
PHP does not require (or support) explicit type definition in variable declaration; a variable's type is determined by the context in which that variable is used. That is to say, if you assign a string value to variable var, var becomes a string. If you then assign an integer value to var, it becomes an integer.
An example of PHP's automatic type conversion is the addition operator '+'. If any of the operands is a double, then all operands are evaluated as doubles, and the result will be a double. Otherwise, the operands will be interpreted as integers, and the result will also be an integer. Note that this does NOT change the types of the operands themselves; the only change is in how the operands are evaluated.
$foo = "0"; // $foo is string (ASCII 48) $foo++; // $foo is the string "1" (ASCII 49) $foo += 1; // $foo is now an integer (2) $foo = $foo + 1.3; // $foo is now a double (3.3) $foo = 5 + "10 Little Piggies"; // $foo is integer (15) $foo = 5 + "10 Small Pigs"; // $foo is integer (15)
If the last two examples above seem odd, see String conversion.
If you wish to force a variable to be evaluated as a certain type, see the section on Type casting. If you wish to change the type of a variable, see settype().
Type casting in PHP works much as it does in C: the name of the desired type is written in parentheses before the variable which is to be cast.
$foo = 10; // $foo is an integer $bar = (double) $foo; // $bar is a double
The casts allowed are:
(int), (integer) - cast to integer
(real), (double), (float) - cast to double
(string) - cast to string
(array) - cast to array
(object) - cast to object
Note that tabs and spaces are allowed inside the parentheses, so the following are functionally equivalent:
$foo = (int) $bar; $foo = ( int ) $bar;
The scope of a variable is the context within which it is defined. For the most part all PHP variables only have a single scope. However, within user-defined functions a local function scope is introduced. Any variable used inside a function is by default limited to the local function scope. For example:
$a = 1; /* global scope */ Function Test () { echo $a; /* reference to local scope variable */ } Test ();
This script will not produce any output because the echo statement refers to a local version of the $a variable, and it has not been assigned a value within this scope. You may notice that this is a little bit different from the C language in that global variables in C are automatically available to functions unless specifically overridden by a local definition. This can cause some problems in that people may inadvertently change a global variable. In PHP global variables must be declared global inside a function if they are going to be used in that function. An example:
$a = 1; $b = 2; Function Sum () { global $a, $b; $b = $a + $b; } Sum (); echo $b;
The above script will output "3". By declaring $a and $b global within the function, all references to either variable will refer to the global version. There is no limit to the number of global variables that can be manipulated by a function.
A second way to access variables from the global scope is to use the special PHP-defined $GLOBALS array. The previous example can be rewritten as:
$a = 1; $b = 2; Function Sum () { $GLOBALS["b"] = $GLOBALS["a"] + $GLOBALS["b"]; } Sum (); echo $b;
The $GLOBALS array is an associative array with the name of the global variable being the key and the contents of that variable being the value of the array element.
Another important feature of variable scoping is the static variable. A static variable exists only in a local function scope, but it does not lose its value when program execution leaves this scope. Consider the following example:
Function Test () { $a = 0; echo $a; $a++; }
This function is quite useless since every time it is called it sets $a to 0 and prints "0". The $a++ which increments the variable serves no purpose since as soon as the function exits the $a variable disappears. To make a useful counting function which will not lose track of the current count, the $a variable is declared static:
Function Test () { static $a = 0; echo $a; $a++; }
Now, every time the Test() function is called it will print the value of $a and increment it.
Static variables are also essential when functions are called recursively. A recursive function is one which calls itself. Care must be taken when writing a recursive function because it is possible to make it recurse indefinitely. You must make sure you have an adequate way of terminating the recursion. The following simple function recursively counts to 10:
Function Test () { static $count = 0; $count++; echo $count; if ($count < 10) { Test (); } $count--; }
Sometimes it is convenient to be able to have variable variable names. That is, a variable name which can be set and used dynamically. A normal variable is set with a statement such as:
$a = "hello";
A variable variable takes the value of a variable and treats that as the name of a variable. In the above example, hello, can be used as the name of a variable by using two dollar signs. ie.
$$a = "world";
At this point two variables have been defined and stored in the PHP symbol tree: $a with contents "hello" and $hello with contents "world". Therefore, this statement:
echo "$a ${$a}";
produces the exact same output as:
echo "$a $hello";
ie. they both produce: hello world.
In order to use variable variables with arrays, you have to resolve an ambiguity problem. That is, if you write $$a[1] then the parser needs to know if you meant to use $a[1] as a variable, or if you wanted $$a as the variable and then the [1] index from that variable. The syntax for resolving this ambiguity is: ${$a[1]} for the first case and ${$a}[1] for the second.
When a form is submitted to a PHP script, any variables from that form will be automatically made available to the script by PHP. For instance, consider the following form:
Example 7-1. Simple form variable <form action="foo.php3" method="post"> Name: <input type="text" name="name"><br> <input type="submit"> </form> |
When submitted, PHP will create the variable $name, which will will contain whatever what entered into the Name: field on the form.
PHP also understands arrays in the context of form variables, but only in one dimension. You may, for example, group related variables together, or use this feature to retrieve values from a multiple select input:
Example 7-2. More complex form variables <form action="array.php" method="post"> Name: <input type="text" name="personal[name]"><br> Email: <input type="text" name="personal[email]"><br> Beer: <br> <select multiple name="beer[]"> <option value="warthog">Warthog <option value="guinness">Guinness </select> <input type="submit"> </form> |
If PHP's track_vars feature is turned on, either by the track_vars configuration setting or the <?php_track_vars?> directive, then variables submitted via the POST or GET methods will also be found in the global associative arrays $HTTP_POST_VARS and $HTTP_GET_VARS as appropriate.
When submitting a form, it is possible to use an image instead of the standard submit button with a tag like:
<input type=image src="image.gif" name="sub">
When the user clicks somewhere on the image, the accompanying form will be transmitted to the server with two additional variables, sub_x and sub_y. These contain the coordinates of the user click within the image. The experienced may note that the actual variable names sent by the browser contains a period rather than an underscore, but PHP converts the period to an underscore automatically.
PHP transparently supports HTTP cookies as defined by Netscape's Spec. Cookies are a mechanism for storing data in the remote browser and thus tracking or identifying return users. You can set cookies using the SetCookie() function. Cookies are part of the HTTP header, so the SetCookie function must be called before any output is sent to the browser. This is the same restriction as for the Header() function. Any cookies sent to you from the client will automatically be turned into a PHP variable just like GET and POST method data.
If you wish to assign multiple values to a single cookie, just add [] to the cookie name. For example:
SetCookie ("MyCookie[]", "Testing", time()+3600);
Note that a cookie will replace a previous cookie by the same name in your browser unless the path or domain is different. So, for a shopping cart application you may want to keep a counter and pass this along. i.e.
Example 7-3. SetCookie Example $Count++; SetCookie ("Count", $Count, time()+3600); SetCookie ("Cart[$Count]", $item, time()+3600); |
PHP automatically makes environment variables available as normal PHP variables.
echo $HOME; /* Shows the HOME environment variable, if set. */
Since information coming in via GET, POST and Cookie mechanisms also automatically create PHP variables, it is sometimes best to explicitly read a variable from the environment in order to make sure that you are getting the right version. The getenv() function can be used for this. You can also set an environment variable with the putenv() function.
Because PHP determines the types of variables and converts them (generally) as needed, it is not always obvious what type a given variable is at any one time. PHP includes several functions which find out what type a variable is. They are gettype(), is_long(), is_double(), is_string(), is_array(), and is_object().
PHP defines several constants and provides a mechanism for defining more at run-time. Constants are much like variables, save for the two facts that constants must be defined using the define() function, and that they cannot later be redefined to another value.
The predefined constants (always available) are:
The name of the script file presently being parsed. If used within a file which has been included or required, then the name of the included file is given, and not the name of the parent file.
The number of the line within the current script file which is being parsed. If used within a file which has been included or required, then the position within the included file is given.
The string representation of the version of the PHP parser presently in use; e.g. '3.0.8-dev'.
The name of the operating system on which the PHP parser is executing; e.g. 'Linux'.
A true value.
A false value.
Denotes an error other than a parsing error from which recovery is not possible.
Denotes a condition where PHP knows something is wrong, but will continue anyway; these can be caught by the script itself. An example would be an invalid regexp in ereg().
The parser choked on invalid syntax in the script file. Recovery is not possible.
Something happened which may or may not be an error. Execution continues. Examples include using an unquoted string as a hash index, or accessing a variable which has not been set.
The E_* constants are typically used with the error_reporting() function for setting the error reporting level.
You can define additional constants using the define() function.
Note that these are constants, not C-style macros; only valid scalar data may be represented by a constant.
Example 8-1. Defining Constants <?php define("CONSTANT", "Hello world."); echo CONSTANT; // outputs "Hello world." ?> |
Example 8-2. Using __FILE__ and __LINE__ <?php function report_error($file, $line, $message) { echo "An error occured in $file on line $line: $message."; } report_error(__FILE__,__LINE__, "Something went wrong!"); ?> |
Expressions are the most important building stones of PHP. In PHP, almost anything you write is an expression. The simplest yet most accurate way to define an expression is "anything that has a value".
The most basic forms of expressions are constants and variables. When you type "$a = 5", you're assigning '5' into $a. '5', obviously, has the value 5, or in other words '5' is an expression with the value of 5 (in this case, '5' is an integer constant).
After this assignment, you'd expect $a's value to be 5 as well, so if you wrote $b = $a, you'd expect it to behave just as if you wrote $b = 5. In other words, $a is an expression with the value of 5 as well. If everything works right, this is exactly what will happen.
Slightly more complex examples for expressions are functions. For instance, consider the following function:
function foo () { return 5; }
Assuming you're familiar with the concept of functions (if you're not, take a look at the chapter about functions), you'd assume that typing $c = foo() is essentially just like writing $c = 5, and you're right. Functions are expressions with the value of their return value. Since foo() returns 5, the value of the expression 'foo()' is 5. Usually functions don't just return a static value but compute something.
Of course, values in PHP don't have to be integers, and very often they aren't. PHP supports three scalar value types: integer values, floating point values and string values (scalar values are values that you can't 'break' into smaller pieces, unlike arrays, for instance). PHP also supports two composite (non-scalar) types: arrays and objects. Each of these value types can be assigned into variables or returned from functions.
So far, users of PHP/FI 2 shouldn't feel any change. However, PHP takes expressions much further, in the same way many other languages do. PHP is an expression-oriented language, in the sense that almost everything is an expression. Consider the example we've already dealt with, '$a = 5'. It's easy to see that there are two values involved here, the value of the integer constant '5', and the value of $a which is being updated to 5 as well. But the truth is that there's one additional value involved here, and that's the value of the assignment itself. The assignment itself evaluates to the assigned value, in this case 5. In practice, it means that '$a = 5', regardless of what it does, is an expression with the value 5. Thus, writing something like '$b = ($a = 5)' is like writing '$a = 5; $b = 5;' (a semicolon marks the end of a statement). Since assignments are parsed in a right to left order, you can also write '$b = $a = 5'.
Another good example of expression orientation is pre- and post-increment and decrement. Users of PHP/FI 2 and many other languages may be familiar with the notation of variable++ and variable--. These are increment and decrement operators. In PHP/FI 2, the statement '$a++' has no value (is not an expression), and thus you can't assign it or use it in any way. PHP enhances the increment/decrement capabilities by making these expressions as well, like in C. In PHP, like in C, there are two types of increment - pre-increment and post-increment. Both pre-increment and post-increment essentially increment the variable, and the effect on the variable is idential. The difference is with the value of the increment expression. Pre-increment, which is written '++$variable', evaluates to the incremented value (PHP increments the variable before reading its value, thus the name 'pre-increment'). Post-increment, which is written '$variable++' evaluates to the original value of $variable, before it was incremented (PHP increments the variable after reading its value, thus the name 'post-increment').
A very common type of expressions are comparison expressions. These expressions evaluate to either 0 or 1, meaning FALSE or TRUE (respectively). PHP supports > (bigger than), >= (bigger than or equal to), == (equal), != (not equal), < (smaller than) and <= (smaller than or equal to). These expressions are most commonly used inside conditional execution, such as if statements.
The last example of expressions we'll deal with here is combined operator-assignment expressions. You already know that if you want to increment $a by 1, you can simply write '$a++' or '++$a'. But what if you want to add more than one to it, for instance 3? You could write '$a++' multiple times, but this is obviously not a very efficient or comfortable way. A much more common practice is to write '$a = $a + 3'. '$a + 3' evaluates to the value of $a plus 3, and is assigned back into $a, which results in incrementing $a by 3. In PHP, as in several other languages like C, you can write this in a shorter way, which with time would become clearer and quicker to understand as well. Adding 3 to the current value of $a can be written '$a += 3'. This means exactly "take the value of $a, add 3 to it, and assign it back into $a". In addition to being shorter and clearer, this also results in faster execution. The value of '$a += 3', like the value of a regular assignment, is the assigned value. Notice that it is NOT 3, but the combined value of $a plus 3 (this is the value that's assigned into $a). Any two-place operator can be used in this operator-assignment mode, for example '$a -= 5' (subtract 5 from the value of $a), '$b *= 7' (multiply the value of $b by 7), etc.
There is one more expression that may seem odd if you haven't seen it in other languages, the ternary conditional operator:
$first ? $second : $third
The following example should help you understand pre- and post-increment and expressions in general a bit better:
function double($i) { return $i*2; } $b = $a = 5; /* assign the value five into the variable $a and $b */ $c = $a++; /* post-increment, assign original value of $a (5) to $c */ $e = $d = ++$b; /* pre-increment, assign the incremented value of $b (6) to $d and $e */ /* at this point, both $d and $e are equal to 6 */ $f = double($d++); /* assign twice the value of $d before the increment, 2*6 = 12 to $f */ $g = double(++$e); /* assign twice the value of $e after the increment, 2*7 = 14 to $g */ $h = $g += 10; /* first, $g is incremented by 10 and ends with the value of 24. the value of the assignment (24) is then assigned into $h, and $h ends with the value of 24 as well. */
In the beginning of the chapter we said that we'll be describing the various statement types, and as promised, expressions can be statements. However, not every expression is a statement. In this case, a statement has the form of 'expr' ';' that is, an expression followed by a semicolon. In '$b=$a=5;', $a=5 is a valid expression, but it's not a statement by itself. '$b=$a=5;' however is a valid statement.
One last thing worth mentioning is the truth value of expressions. In many events, mainly in conditional execution and loops, you're not interested in the specific value of the expression, but only care about whether it means TRUE or FALSE (PHP doesn't have a dedicated boolean type). The truth value of expressions in PHP is calculated in a similar way to perl. Any numeric non-zero numeric value is TRUE, zero is FALSE. Be sure to note that negative values are non-zero and are thus considered TRUE! The empty string and the string "0" are FALSE; all other strings are TRUE. With non-scalar values (arrays and objects) - if the value contains no elements it's considered FALSE, otherwise it's considered TRUE.
PHP provides a full and powerful implementation of expressions, and documenting it entirely goes beyond the scope of this manual. The above examples should give you a good idea about what expressions are and how you can construct useful expressions. Throughout the rest of this manual we'll write expr to indicate any valid PHP expression.
Remember basic arithmetic from school? These work just like those.
Table 10-1. Arithmetic Operators
example | name | result |
---|---|---|
$a + $b | Addition | Sum of $a and $b. |
$a - $b | Subtraction | Remainder of $b subtracted from $a. |
$a * $b | Multiplication | Product of $a and $b. |
$a / $b | Division | Dividend of $a and $b. |
$a % $b | Modulus | Remainder of $a divided by $b. |
There is only really one string operator -- the concatenation operator (".").
$a = "Hello "; $b = $a . "World!"; // now $b = "Hello World!"
The basic assignment operator is "=". Your first inclination might be to think of this as "equal to". Don't. It really means that the the left operand gets set to the value of the expression on the rights (that is, "gets set to").
The value of an assignment expression is the value assigned. That is, the value of "$a = 3" is 3. This allows you to do some tricky things:
$a = ($b = 4) + 5; // $a is equal to 9 now, and $b has been set to 4.
In addition to the basic assignment operator, there are "combined operators" for all of the binary arithmetic and string operators that allow you to use a value in an expression and then set its value to the result of that expression. For example:
$a = 3; $a += 5; // sets $a to 8, as if we had said: $a = $a + 5; $b = "Hello "; $b .= "There!"; // sets $b to "Hello There!", just like $b = $b . "There!";
Bitwise operators allow you to turn specific bits within an integer on or off.
Table 10-2. Bitwise Operators
example | name | result |
---|---|---|
$a & $b | And | Bits that are set in both $a and $b are set. |
$a | $b | Or | Bits that are set in either $a or $b are set. |
$a ^ $b | Xor | Bits that are set in $a or $b but not both are set. |
~ $a | Not | Bits that are set in $a are not set, and vice versa. |
$a << $b | Shift left | Shift the bits of $a $b steps to the left (each step means "multiply by two") |
$a >> $b | Shift right | Shift the bits of $a $b steps to the right (each step means "divide by two") |
Table 10-3. Logical Operators
example | name | result |
---|---|---|
$a and $b | And | True of both $a and $b are true. |
$a or $b | Or | True if either $a or $b is true. |
$a xor $b | Or | True if either $a or $b is true, but not both. |
! $a | Not | True if $a is not true. |
$a && $b | And | True of both $a and $b are true. |
$a || $b | Or | True if either $a or $b is true. |
The reason for the two different variations of "and" and "or" operators is that they operate at different precedences. (See below.)
Comparison operators, as their name imply, allow you to compare two values.
Table 10-4. Comparson Operators
example | name | result |
---|---|---|
$a == $b | Equal | True if $a is equal to $b. |
$a != $b | Not equal | True if $a is not equal to $b. |
$a < $b | Less than | True if $a is strictly less than $b. |
$a > $b | Greater than | True if $a is strictly greater than $b. |
$a <= $b | Less than or equal to | True if $a is less than or equal to $b. |
$a >= $b | Greater than or equal to | True if $a is greater than or equal to $b. |
Another conditional operator is the "?:" (or trinary) operator, which operates as in C and many other languages.
(expr1) ? (expr2) : (expr3);
The precedence of an operator specifies how "tightly" it binds two expressions together. For example, in the expression 1 + 5 * 3, the answer is 16 and not 18 because the multiplication ("*") operator has a higher precedence than the addition ("+") operator.
The following table lists the precedence of operators with the lowest-precedence operators listed first.
Table 10-5. Operator Precedence
Associativity | Operators |
---|---|
left | , |
left | or |
left | xor |
left | and |
right | |
left | = += -= *= /= .= %= &= != ~= <<= >>= |
left | ? : |
left | || |
left | && |
left | | |
left | ^ |
left | & |
non-associative | == != |
non-associative | < <= > >= |
left | << >> |
left | + - . |
left | * / % |
right | ! ~ ++ -- (int) (double) (string) (array) (object) @ |
right | [ |
non-associative | new |
Any PHP script is built out of a series of statements. A statement can be an assignment, a function call, a loop, a conditional statement of even a statement that does nothing (an empty statement). Statements usually end with a semicolon. In addition, statements can be grouped into a statement-group by encapsulating a group of statements with curly braces. A statement-group is a statement by itself as well. The various statement types are described in this chapter.
The if construct is one of the most important features of many languages, PHP included. It allows for conditional execution of code fragments. PHP features an if structure that is similar to that of C:
if (expr) statement
As described in the section about expressions, expr is evaluated to its truth value. If expr evaluates to TRUE, PHP will execute statement, and if it evaluates to FALSE - it'll ignore it.
The following example would display a is bigger than b if $a is bigger than $b:
if ($a > $b) print "a is bigger than b";
Often you'd want to have more than one statement to be executed conditionally. Of course, there's no need to wrap each statement with an if clause. Instead, you can group several statements into a statement group. For example, this code would display a is bigger than b if $a is bigger than $b, and would then assign the value of $a into $b:
if ($a > $b) { print "a is bigger than b"; $b = $a; }
If statements can be nested indefinitely within other if statements, which provides you with complete flexibility for conditional execution of the various parts of your program.
Often you'd want to execute a statement if a certain condition is met, and a different statement if the condition is not met. This is what else is for. else extends an if statement to execute a statement in case the expression in the if statement evaluates to FALSE. For example, the following code would display a is bigger than b if $a is bigger than $b, and a is NOT bigger than b otherwise:
if ($a > $b) { print "a is bigger than b"; } else { print "a is NOT bigger than b"; }
elseif, as its name suggests, is a combination of if and else. Like else, it extends an if statement to execute a different statement in case the original if expression evaluates to FALSE. However, unlike else, it will execute that alternative expression only if the elseif conditional expression evaluates to TRUE. For example, the following code would display a is bigger than b, a equal to b or a is smaller than b:
if ($a > $b) { print "a is bigger than b"; } elseif ($a == $b) { print "a is equal to b"; } else { print "a is smaller than b"; }
There may be several elseifs within the same if statement. The first elseif expression (if any) that evaluates to true would be executed. In PHP, you can also write 'else if' (in two words) and the behavior would be identical to the one of 'elseif' (in a single word). The syntactic meaning is slightly different (if you're familiar with C, this is the same behavior) but the bottom line is that both would result in exactly the same behavior.
The elseif statement is only executed if the preceding if expression and any preceding elseif expressions evaluated to FALSE, and the current elseif expression evaluated to TRUE.
PHP offers a different way to group statements within an if statement. This is most commonly used when you nest HTML blocks inside if statements, but can be used anywhere. Instead of using curly braces, if (expr) should be followed by a colon, the list of one or more statements, and end with endif;. Consider the following example:
<?php if ($a==5): ?> A = 5 <?php endif; ?>
In the above example, the HTML block "A = 5" is nested within an if statement written in the alternative syntax. The HTML block would be displayed only if $a is equal to 5.
The alternative syntax applies to else and elseif as well. The following is an if structure with elseif and else in the alternative format:
if ($a == 5): print "a equals 5"; print "..."; elseif ($a == 6): print "a equals 6"; print "!!!"; else: print "a is neither 5 nor 6"; endif;
while loops are the simplest type of loop in PHP. They behave just like their C counterparts. The basic form of a while statement is:
while (expr) statement
The meaning of a while statement is simple. It tells PHP to execute the nested statement(s) repeatedly, as long as the while expression evaluates to TRUE. The value of the expression is checked each time at the beginning of the loop, so even if this value changes during the execution of the nested statement(s), execution will not stop until the end of the iteration (each time PHP runs the statements in the loop is one iteration). Sometimes, if the while expression evaluates to FALSE from the very beginning, the nested statement(s) won't even be run once.
Like with the if statement, you can group multiple statements within the same while loop by surrounding a group of statements with curly braces, or by using the alternate syntax:
while (expr): statement ... endwhile;
The following examples are identical, and both print numbers from 1 to 10:
/* example 1 */ $i = 1; while ($i <= 10) { print $i++; /* the printed value would be $i before the increment (post-increment) */ } /* example 2 */ $i = 1; while ($i <= 10): print $i; $i++; endwhile;
do..while loops are very similar to while loops, except the truth expression is checked at the end of each iteration instead of in the beginning. The main difference from regular while loops is that the first iteration of a do..while loop is guarenteed to run (the truth expression is only checked at the end of the iteration), whereas it's may not necessarily run with a regular while loop (the truth expression is checked at the beginning of each iteration, if it evaluates to FALSE right from the beginning, the loop execution would end immediately).
There is just one syntax for do..while loops:
$i = 0; do { print $i; } while ($i>0);
The above loop would run one time exactly, since after the first iteration, when truth expression is checked, it evaluates to FALSE ($i is not bigger than 0) and the loop execution ends.
Advanced C users may be familiar with a different usage of the do..while loop, to allow stopping execution in the middle of code blocks, by encapsulating them with do..while(0), and using the break statement. The following code fragment demonstrates this:
do { if ($i < 5) { print "i is not big enough"; break; } $i *= $factor; if ($i < $minimum_limit) { break; } print "i is ok"; ...process i... } while(0);
Don't worry if you don't understand this right away or at all. You can code scripts and even powerful scripts without using this `feature'.
for loops are the most complex loops in PHP. They behave like their C counterparts. The syntax of a for loop is:
for (expr1; expr2; expr3) statement
The first expression (expr1) is evaluated (executed) once unconditionally at the beginning of the loop.
In the beginning of each iteration, expr2 is evaluated. If it evaluates to TRUE, the loop continues and the nested statement(s) are executed. If it evaluates to FALSE, the execution of the loop ends.
At the end of each iteration, expr3 is evaluated (executed).
Each of the expressions can be empty. expr2 being empty means the loop should be run indefinitely (PHP implicitly considers it as TRUE, like C). This may not be as useless as you might think, since often you'd want to end the loop using a conditional break statement instead of using the for truth expression.
Consider the following examples. All of them display numbers from 1 to 10:
/* example 1 */ for ($i = 1; $i <= 10; $i++) { print $i; } /* example 2 */ for ($i = 1;;$i++) { if ($i > 10) { break; } print $i; } /* example 3 */ $i = 1; for (;;) { if ($i > 10) { break; } print $i; $i++; } /* example 4 */ for ($i = 1; $i <= 10; print $i, $i++) ;
Of course, the first example appears to be the nicest one (or perhaps the fourth), but you may find that being able to use empty expressions in for loops comes in handy in many occasions.
PHP also supports the alternate "colon syntax" for for loops.
for (expr1; expr2; expr3): statement; ...; endfor;
Other languages have a foreach statement to traverse an array or hash. PHP uses the while statement and the list() and each() functions for this. See the documentation for these functions for an example.
break breaks out of the current looping control-structures.
$i = 0; while ($i < 10) { if ($arr[$i] == "stop") { break; } $i++; }
continue is used within looping structures to skip the rest of the current loop iteration and continue execution at the beginning of the next iteration.
while (list($key,$value) = each($arr)) { if ($key % 2) { // skip even members continue; } do_something_odd ($value); }
The switch statement is similar to a series of IF statements on the same expression. In many occasions, you may want to compare the same variable (or expression) with many different values, and execute a different piece of code depending on which value it equals to. This is exactly what the switch statement is for.
The following two examples are two different ways to write the same thing, one using a series of if statements, and the other using the switch statement:
if ($i == 0) { print "i equals 0"; } if ($i == 1) { print "i equals 1"; } if ($i == 2) { print "i equals 2"; } switch ($i) { case 0: print "i equals 0"; break; case 1: print "i equals 1"; break; case 2: print "i equals 2"; break; }
It is important to understand how the switch statement is executed in order to avoid mistakes. The switch statement executes line by line (actually, statement by statement). In the beginning, no code is executed. Only when a case statement is found with a value that matches the value of the switch expression does PHP begin to execute the statements. PHP continues to execute the statements until the end of the switch block, or the first time it sees a break statement. If you don't write a break statement at the end of a case's statement list, PHP will go on executing the statements of the following case. For example:
switch ($i) { case 0: print "i equals 0"; case 1: print "i equals 1"; case 2: print "i equals 2"; }
Here, if $i equals to 0, PHP would execute all of the print statements! If $i equals to 1, PHP would execute the last two print statements, and only if $i equals to 2, you'd get the 'expected' behavior and only 'i equals 2' would be displayed. So, it's important not to forget break statements (even though you may want to avoid supplying them on purpose under certain circumstances).
The statement list for a case can also be empty, which simply passes control into the statement list for the next case.
switch ($i) { case 0: case 1: case 2: print "i is less than 3 but not negative"; break; case 3: print "i is 3"; }
A special case is the default case. This case matches anything that wasn't matched by the other cases. For example:
switch ($i) { case 0: print "i equals 0"; break; case 1: print "i equals 1"; break; case 2: print "i equals 2"; break; default: print "i is not equal to 0, 1 or 2"; }
The case expression may be any expression that evaluates to a scalar type, that is, integer or floating-point numbers and strings. Arrays or objects are meaningless in that context.
The require statement replaces itself with the specified file, much like the C preprocessor's #include works.
This means that you can't put a require statement inside of a loop structure and expect it to include the contents of a different file on each iteration. To do that, use an include statement.
require 'header.inc';
The include statement includes and evaluates the specified file.
This happens each time the include statement is encountered, so you can use an include statement within a looping structure to include a number of different file.
$files = array ('first.inc', 'second.inc', 'third.inc'); for ($i = 0; $i < count($files); $i++) { include $files[$i]; }
include differs from require in that the include statement is re-evaluated each time it is encountered (and only when it is being executed), whereas the require statement is replaced by the required file when it is first encountered, whether the contents of the file will be evaluated or not (for example, if it is inside an if statement whose condition evaluated to false).
Because include is a special language construct, you must enclose it within a statement block if it is inside a conditional block.
/* This is WRONG and will not work as desired. */ if ($condition) include($file); else include($other); /* This is CORRECT. */ if ($condition) { include($file); } else { include($other); }
When the file is evaluated, the parser begins in "HTML-mode" which will output the contents of the file until the first PHP start tag (<?) is encountered.
See also readfile(), require(), virtual().
A function may be defined using syntax such as the following:
function foo ($arg_1, $arg_2, ..., $arg_n) { echo "Example function.\n"; return $retval; }
Any valid PHP code may appear inside a function, even other functions and class definitions.
Functions must be defined before they are referenced.
Values are returned by using the optional return statement. Any type may be returned, including lists and objects.
function square ($num) { return $num * $num; } echo square (4); // outputs '16'.
You can't return multiple values from a function, but similar results can be obtained by returning a list.
function small_numbers() { return array (0, 1, 2); } list ($zero, $one, $two) = small_numbers();
Information may be passed to functions via the argument list, which is a comma-delimited list of variables and/or constants.
PHP supports passing arguments by value (the default), passing by reference, and default argument values. Variable-length argument lists are not supported, but a similar effect may be obtained by passing arrays.
function takes_array($input) { echo "$input[0] + $input[1] = ", $input[0]+$input[1]; }
By default, function arguments are passed by value (so that if you change the value of the argument within the function, it does not get changed outside of the function). If you wish to allow a function to modify its arguments, you must pass them by reference.
If you want an argument to a function to always be passed by reference, you can prepend an ampersand (&) to the argument name in the function definition:
function add_some_extra(&$string) { $string .= 'and something extra.'; } $str = 'This is a string, '; add_some_extra($str); echo $str; // outputs 'This is a string, and something extra.'
If you wish to pass a variable by reference to a function which does not do this by default, you may prepend an ampersand to the argument name in the function call:
function foo ($bar) { $bar .= ' and something extra.'; } $str = 'This is a string, '; foo ($str); echo $str; // outputs 'This is a string, ' foo (&$str); echo $str; // outputs 'This is a string, and something extra.'
A function may define C++-style default values for scalar arguments as follows:
function makecoffee ($type = "cappucino") { return "Making a cup of $type.\n"; } echo makecoffee (); echo makecoffee ("espresso");
The output from the above snippet is:
Making a cup of cappucino. Making a cup of espresso.
The default value must be a constant expression, not (for example) a variable or class member.
In PHP 4.0 it's also possible to specify unset for default argument. This means that the argument will not be set at all, if a value is not supplied.
Note that when using default arguments, any defaults should be on the right side of any non-default arguments; otherwise, things will not work as expected. Consider the following code snippet:
function makeyogurt ($type = "acidophilus", $flavour) { return "Making a bowl of $type $flavour.\n"; } echo makeyogurt ("raspberry"); // won't work as expected
The output of the above example is:
Warning: Missing argument 2 in call to makeyogurt() in /usr/local/etc/httpd/htdocs/php3test/functest.html on line 41 Making a bowl of raspberry .
Now, compare the above with this:
function makeyogurt ($flavour, $type = "acidophilus") { return "Making a bowl of $type $flavour.\n"; } echo makeyogurt ("raspberry"); // works as expected
The output of this example is:
Making a bowl of acidophilus raspberry.
The old_function statement allows you to declare a function using a syntax identical to PHP/FI2 (except you must replace 'function' with 'old_function'.
This is a deprecated feature, and should only be used by the PHP/FI2->PHP3 convertor.
Warning |
Functions declared as old_function cannot be called from PHP's internal code. Among other things, this means you can't use them in functions such as usort(), array_walk(), and register_shutdown_function(). You can get around this limitation by writing a wrapper function (in normal PHP3 form) to call the old_function. |
A class is a collection of variables and functions working with these variables. A class is defined using the following syntax:
<?php class Cart { var $items; // Items in our shopping cart // Add $num articles of $artnr to the cart function add_item ($artnr, $num) { $this->items[$artnr] += $num; } // Take $num articles of $artnr out of the cart function remove_item ($artnr, $num) { if ($this->items[$artnr] > $num) { $this->items[$artnr] -= $num; return true; } else { return false; } } } ?>
This defines a class named Cart that consists of an associative array of articles in the cart and two functions to add and remove items from this cart.
Classes are types, that is, they are blueprints for actual variables. You have to create a variables of the desired type with the new operator.
$cart = new Cart; $cart->add_item("10", 1);
This creates an object $cart of the class Cart. The function add_item() of that object is being called to add 1 item of article number 10 to the cart.
Classes can be extensions of other classes. The extended or derived class has all variables and functions of the base class and what you add in the extended definition. This is done using the extends keyword.
class Named_Cart extends Cart { var $owner; function set_owner ($name) { $this->owner = $name; } }
This defines a class Named_Cart that has all variables and functions of Cart plus an additional variable $owner and an additional function set_owner(). You create a named cart the usual way and can now set and get the carts owner. You can still use normal cart functions on named carts:
$ncart = new Named_Cart; // Create a named cart $ncart->set_owner ("kris"); // Name that cart print $ncart->owner; // print the cart owners name $ncart->add_item ("10", 1); // (inherited functionality from cart)
Within functions of a class the variable $this means this object. You have to use $this->something to access any variable or function named something within your current object.
Constructors are functions in a class that are automatically called when you create a new instance of a class. A function becomes a constructor when it has the same name as the class.
class Auto_Cart extends Cart { function Auto_Cart () { $this->add_item ("10", 1); } }
This defines a class Auto_Cart that is a Cart plus a constructor which initializes the cart with one item of article number "10" each time a new Auto_Cart is being made with "new". Constructors can also take arguments and these arguments can be optional, which makes them much more useful.
class Constructor_Cart { function Constructor_Cart ($item = "10", $num = 1) { $this->add_item ($item, $num); } } // Shop the same old boring stuff. $default_cart = new Constructor_Cart; // Shop for real... $different_cart = new Constructor_Cart ("20", 17);
Caution |
For derived classes, the constructor of the parent class is not automatically called when the derived class's constructor is called. |
There are 4 types of errors and warnings in PHP. They are:
1 - Normal Function Errors
2 - Normal Warnings
4 - Parser Errors
8 - Notices (warnings you can ignore but which may imply a bug in your code)
The above 4 numbers are added up to define an error reporting level. The default error reporting level is 7 which is 1 + 2 + 4, or everything except notices. This level can be changed in the php3.ini file with the error_reporting directive. It can also be set in your Apache httpd.conf file with the php3_error_reporting directive or lastly it may be set at runtime within a script using the error_reporting() function.
All PHP expressions can also be called with the "@" prefix, which turns off error reporting for that particular expression. If an error occurred during such an expression and the track_errors feature is enabled, you can find the error message in the global variable $php_errormsg.
PHP is not limited to creating just HTML output. It can also be used to create GIF image files, or even more convenient GIF image streams. You will need to compile PHP with the GD library of image functions for this to work.
Example 15-1. GIF creation with PHP <?php Header("Content-type: image/gif"); $string=implode($argv," "); $im = imagecreatefromgif("images/button1.gif"); $orange = ImageColorAllocate($im, 220, 210, 60); $px = (imagesx($im)-7.5*strlen($string))/2; ImageString($im,3,$px,9,$string,$orange); ImageGif($im); ImageDestroy($im); ?> |
The HTTP Authentication hooks in PHP are only available when it is running as an Apache module and is hence not available in the CGI version. In an Apache module PHP script, it is possible to use the Header() function to send an "Authentication Required" message to the client browser causing it to pop up a Username/Password input window. Once the user has filled in a username and a password, the URL containing the PHP script will be called again with the variables, $PHP_AUTH_USER, $PHP_AUTH_PW and $PHP_AUTH_TYPE set to the user name, password and authentication type respectively. Only "Basic" authentication is supported at this point. See the Header() function for more information.
An example script fragment which would force client authentication on a page would be the following:
Example 16-1. HTTP Authentication example <?php if(!isset($PHP_AUTH_USER)) { Header("WWW-Authenticate: Basic realm=\"My Realm\""); Header("HTTP/1.0 401 Unauthorized"); echo "Text to send if user hits Cancel button\n"; exit; } else { echo "Hello $PHP_AUTH_USER.<P>"; echo "You entered $PHP_AUTH_PW as your password.<P>"; } ?> |
Instead of simply printing out the $PHP_AUTH_USER and $PHP_AUTH_PW, you would probably want to check the username and password for validity. Perhaps by sending a query to a database, or by looking up the user in a dbm file.
Watch out for buggy Internet Explorer browsers out there. They seem very picky about the order of the headers. Sending the WWW-Authenticate header before the HTTP/1.0 401 header seems to do the trick for now.
In order to prevent someone from writing a script which reveals the password for a page that was authenticated through a traditional external mechanism, the PHP_AUTH variables will not be set if external authentication is enabled for that particular page. In this case, the $REMOTE_USER variable can be used to identify the externally-authenticated user.
Note, however, that the above does not prevent someone who controls a non-authenticated URL from stealing passwords from authenticated URLs on the same server.
Both Netscape and Internet Explorer will clear the local browser window's authentication cache for the realm upon receiving a server response of 401. This can effectively "log out" a user, forcing them to re-enter their username and password. Some people use this to "time out" logins, or provide a "log-out" button.
Example 16-2. HTTP Authentication example forcing a new name/password <?php function authenticate() { Header( "WWW-authenticate: basic realm='Test Authentication System'"); Header( "HTTP/1.0 401 Unauthorized"); echo "You must enter a valid login ID and password to access this resource\n"; exit; } if(!isset($PHP_AUTH_USER) || ($SeenBefore == 1 && !strcmp($OldAuth, $PHP_AUTH_USER)) ) { authenticate(); } else { echo "Welcome: $PHP_AUTH_USER<BR>"; echo "Old: $OldAuth"; echo "<FORM ACTION=\"$PHP_SELF\" METHOD=POST>\n"; echo "<INPUT TYPE=HIDDEN NAME=\"SeenBefore\" VALUE=\"1\">\n"; echo "<INPUT TYPE=HIDDEN NAME=\"OldAuth\" VALUE=\"$PHP_AUTH_USER\">\n"; echo "<INPUT TYPE=Submit VALUE=\"Re Authenticate\">\n"; echo "</FORM>\n"; } ?> |
This behavior is not required by the HTTP Basic authentication standard, so you should never depend on this. Testing with Lynx has shown that Lynx does not clear the authentication credentials with a 401 server response, so pressing back and then forward again will open the resource (as long as the credential requirements haven't changed).
Also note that this does not work using Microsoft's IIS server and the CGI version of PHP due to a limitation of IIS.
PHP transparently supports HTTP cookies. Cookies are a mechanism for storing data in the remote browser and thus tracking or identifying return users. You can set cookies using the setcookie() function. Cookies are part of the HTTP header, so setcookie() must be called before any output is sent to the browser. This is the same limitation that header() has.
Any cookies sent to you from the client will automatically be turned into a PHP variable just like GET and POST method data. If you wish to assign multiple values to a single cookie, just add [] to the cookie name. For more details see the setcookie() function.
PHP is capable of receiving file uploads from any RFC-1867 compliant browser (which includes Netscape Navigator 3 or later, Microsoft Internet Explorer 3 with a patch from Microsoft, or later without a patch). This feature lets people upload both text and binary files. With PHP's authentication and file manipulation functions, you have full control over who is allowed to upload and what is to be done with the file once it has been uploaded.
Note that PHP also supports PUT-method file uploads as used by Netscape Composer and W3C's Amaya clients. See the PUT Method Support for more details.
A file upload screen can be built by creating a special form which looks something like this:
Example 18-1. File Upload Form <FORM ENCTYPE="multipart/form-data" ACTION="_URL_" METHOD=POST> <INPUT TYPE="hidden" name="MAX_FILE_SIZE" value="1000"> Send this file: <INPUT NAME="userfile" TYPE="file"> <INPUT TYPE="submit" VALUE="Send File"> </FORM> |
$userfile - The temporary filename in which the uploaded file was stored on the server machine.
$userfile_name - The original name of the file on the sender's system.
$userfile_size - The size of the uploaded file in bytes.
$userfile_type - The mime type of the file if the browser provided this information. An example would be "image/gif".
Files will by default be stored in the server's default temporary directory. This can be changed by setting the environment variable TMPDIR in the environment in which PHP runs. Setting it using putenv() from within a PHP script will not work.
The PHP script which receives the uploaded file should implement whatever logic is necessary for determining what should be done with the uploaded file. You can for example use the $file_size variable to throw away any files that are either too small or too big. You could use the $file_type variable to throw away any files that didn't match a certain type criteria. Whatever the logic, you should either delete the file from the temporary directory or move it elsewhere.
The file will be deleted from the temporary directory at the end of the request if it has not been moved away or renamed.
The MAX_FILE_SIZE item cannot specify a file size greater than the file size that has been set in the upload_max_filesize in the PHP3.ini file or the corresponding php3_upload_max_filesize Apache .conf directive. The default is 2 Megabytes.
Please note that the CERN httpd seems to strip off everything starting at the first whitespace in the content-type mime header it gets from the client. As long as this is the case, CERN httpd will not support the file upload feature.
It is possible to upload multiple files simultaneously and have the information organized automatically in arrays for you. To do so, you need to use the same array submission syntax in the HTML form as you do with multiple selects and checkboxes:
Note: Support for multiple file uploads was added in version 3.0.10.
Example 18-2. Uploading multiple forms <form action="file-upload.html" method="post" enctype="multipart/form-data"> Send these files:<br> <input name="userfile[]" type="file"><br> <input name="userfile[]" type="file"><br> <input type="submit" value="Send files"> </form> |
When the above form is submitted, the arrays $userfile, $userfile_name, and $userfile_size will be formed in the global scope (as well as in $HTTP_POST_VARS). Each of these will be a numerically indexed array of the appropriate values for the submitted files.
For instance, assume that the filenames /home/test/review.html and /home/test/xwp.out are submitted. In this case, $userfile_name[0] would contain the value review.html, and $userfile_name[1] would contain the value xwp.out. Similarly, $userfile_size[0] would contain review.html's filesize, and so forth.
PHP provides support for the HTTP PUT method used by clients such as Netscape Composer and W3C Amaya. PUT requests are much simpler than a file upload and they look something like this:
PUT /path/filename.html HTTP/1.1
This would normally mean that the remote client would like to save the content that follows as: /path/filename.html in your web tree. It is obviously not a good idea for Apache or PHP to automatically let everybody overwrite any files in your web tree. So, to handle such a request you have to first tell your web server that you want a certain PHP script to handle the request. In Apache you do this with the Script directive. It can be placed almost anywhere in your Apache configuration file. A common place is inside a <Directory> block or perhaps inside a <Virtualhost> block. A line like this would do the trick:
Script PUT /put.php3
This tells Apache to send all PUT requests for URIs that match the context in which you put this line to the put.php3 script. This assumes, of course, that you have PHP enabled for the .php3 extension and PHP is active.
Inside your put.php3 file you would then do something like this:
<? copy($PHP_UPLOADED_FILE_NAME,$DOCUMENT_ROOT.$REQUEST_URI); ?>
This would copy the file to the location requested by the remote client. You would probably want to perform some checks and/or authenticate the user before performing this file copy. The only trick here is that when PHP sees a PUT-method request it stores the uploaded file in a temporary file just like those handled bu the POST-method. When the request ends, this temporary file is deleted. So, your PUT handling PHP script has to copy that file somewhere. The filename of this temporary file is in the $PHP_PUT_FILENAME variable, and you can see the suggested destination filename in the $REQUEST_URI (may vary on non-Apache web servers). This destination filename is the one that the remote client specified. You do not have to listen to this client. You could, for example, copy all uploaded files to a special uploads directory.
As long as support for the "URL fopen wrapper" is enabled when you configure PHP (which it is unless you explicitly pass the --disable-url-fopen-wrapper flag to configure), you can use HTTP and FTP URLs with most functions that take a filename as a parameter, including the require() and include() statements.
For example, you can use this to open a file on a remote web server, parse the output for the data you want, and then use that data in a database query, or simply to output it in a style matching the rest of your website.
Example 19-1. Getting the title of a remote page <?php $file = fopen("http://www.php.net/", "r"); if (!$file) { echo "<p>Unable to open remote file.\n"; exit; } while (!feof($file)) { $line = fgets($file, 1024); /* This only works if the title and its tags are on one line. */ if (eregi("<title>(.*)</title>", $line, $out)) { $title = $out[1]; break; } } fclose($file); ?> |
You can also write to files on an FTP as long you connect as a user with the correct access rights, and the file doesn't exist already. To connect as a user other than 'anonymous', you need to specify the username (and possibly password) within the URL, such as 'ftp://user:password@ftp.example.com/path/to/file'. (You can use the same sort of syntax to access files via HTTP when they require Basic authentication.)
Example 19-2. Storing data on a remote server <?php $file = fopen("ftp://ftp.php.net/incoming/outputfile", "w"); if (!$file) { echo "<p>Unable to open remote file for writing.\n"; exit; } /* Write the data here. */ fputs($file, "$HTTP_USER_AGENT\n"); fclose($file); ?> |
Note: You might get the idea from the example above to use this technique to write to a remote log, but as mentioned above, you can only write to a new file using the URL fopen() wrappers. To do distributed logging like that, you should take a look at syslog().
Note: The following applies to 3.0.7 and later.
Internally in PHP a connection status is maintained. There are 3 possible states:
0 - NORMAL
1 - ABORTED
2 - TIMEOUT
When a PHP script is running normally the NORMAL state, is active. If the remote client disconnects the ABORTED state flag is turned on. A remote client disconnect is usually caused by the user hitting his STOP button. If the PHP-imposed time limit (see set_time_limit()) is hit, the TIMEOUT state flag is turned on.
You can decide whether or not you want a client disconnect to cause your script to be aborted. Sometimes it is handy to always have your scripts run to completion even if there is no remote browser receiving the output. The default behaviour is however for your script to be aborted when the remote client disconnects. This behaviour can be set via the ignore_user_abort php3.ini directive as well as through the corresponding php3_ignore_user_abort Apache .conf directive or with the ignore_user_abort() function. If you do not tell PHP to ignore a user abort and the user aborts, your script will terminate. The one exception is if you have registered a shutdown function using register_shutdown_function(). With a shutdown function, when the remote user hits his STOP button, the next time your script tries to output something PHP will detect that the connection has been aborted and the shutdown function is called. This shutdown function will also get called at the end of your script terminating normally, so to do something different in case of a client diconnect you can use the connection_aborted() function. This function will return true if the connection was aborted.
Your script can also be terminated by the built-in script timer. The default timeout is 30 seconds. It can be changed using the max_execution_time php3.ini directive or the corresponding php3_max_execution_time Apache .conf directive as well as with the set_time_limit() function. When the timer expires the script will be aborted and as with the above client disconnect case, if a shutdown function has been registered it will be called. Within this shutdown function you can check to see if a timeout caused the shutdown function to be called by calling the connection_timeout() function. This function will return true if a timeout caused the shutdown function to be called.
One thing to note is that both the ABORTED and the TIMEOUT states can be active at the same time. This is possible if you tell PHP to ignore user aborts. PHP will still note the fact that a user may have broken the connection, but the script will keep running. If it then hits the time limit it will be aborted and your shutdown function, if any, will be called. At this point you will find that connection_timeout() and connection_aborted() return true. You can also check both states in a single call by using the connection_status(). This function returns a bitfield of the active states. So, if both states are active it would return 3, for example.
Persistent connections are SQL links that do not close when the execution of your script ends. When a persistent connection is requested, PHP checks if there's already an identical persistent connection (that remained open from earlier) - and if it exists, it uses it. If it does not exist, it creates the link. An 'identical' connection is a connection that was opened to the same host, with the same username and the same password (where applicable).
People who aren't thoroughly familiar with the way web servers work and distribute the load may mistake persistent connects for what they're not. In particular, they do not give you an ability to open 'user sessions' on the same SQL link, they do not give you an ability to build up a transaction efficently, and they don't do a whole lot of other things. In fact, to be extremely clear about the subject, persistent connections don't give you any functionality that wasn't possible with their non-persistent brothers.
Why?
This has to do with the way web servers work. There are three ways in which your web server can utilize PHP to generate web pages.
The first method is to use PHP as a CGI "wrapper". When run this way, an instance of the PHP interpreter is created and destroyed for every page request (for a PHP page) to your web server. Because it is destroyed after every request, any resources that it acquires (such as a link to an SQL database server) are closed when it is destroyed. In this case, you do not gain anything from trying to use persistent connections -- they simply don't persist.
The second, and most popular, method is to run PHP as a module in a multiprocess web server, which currently only includes Apache. A multiprocess server typically has one process (the parent) which coordinates a set of processes (its children) who actually do the work of serving up web pages. When each request comes in from a a client, it is handed off to one of the children that is not already serving another client. This means that when the same client makes a second request to the server, it may be serviced by a different child process than the first time. What a persistent connection does for you in this case it make it so each child process only needs to connect to your SQL server the first time that it serves a page that makes us of such a connection. When another page then requires a connection to the SQL server, it can reuse the connection that child established earlier.
The last method is to use PHP as a plug-in for a multithreaded web server. Currently this is only theoretical -- PHP does not yet work as a plug-in for any multithreaded web servers. Work is progressing on support for ISAPI, WSAPI, and NSAPI (on Windows), which will all allow PHP to be used as a plug-in on multithreaded servers like Netscape FastTrack, Microsoft's Internet Information Server (IIS), and O'Reilly's WebSite Pro. When this happens, the behavior will be essentially the same as for the multiprocess model described before.
If persistent connections don't have any added functionality, what are they good for?
The answer here is extremely simple -- efficiency. Persistent connections are good if the overhead to create a link to your SQL server is high. Whether or not this overhead is really high depends on many factors. Like, what kind of database it is, whether or not it sits on the same computer on which your web server sits, how loaded the machine the SQL server sits on is and so forth. The bottom line is that if that connection overhead is high, persistent connections help you considerably. They cause the child process to simply connect only once for its entire lifespan, instead of every time it processes a page that requires connecting to the SQL server. This means that for every child that opened a persistent connection will have its own open persistent connection to the server. For example, if you had 20 different child processes that ran a script that made a persistent connection to your SQL server, you'd have 20 different connections to the SQL server, one from each child.
An important summary. Persistent connections were designed to have one-to-one mapping to regular connections. That means that you should always be able to replace persistent connections with non-persistent connections, and it won't change the way your script behaves. It may (and probably will) change the efficiency of the script, but not its behavior!
The Adabas D functions are deprecated, you probably want to use the Unified ODBC functions instead.
class apache_lookup_uri
(string filename);This performs a partial request for a URI. It goes just far enough to obtain all the important information about the given resource and returns this information in a class. The properties of the returned class are:
status |
the_request |
status_line |
method |
content_type |
handler |
uri |
filename |
path_info |
args |
boundary |
no_cache |
no_local_copy |
allowed |
send_bodyct |
bytes_sent |
byterange |
clength |
unparsed_uri |
mtime |
request_time |
Note: Note: apache_lookup_uri only works when PHP is installed as an Apache module
string apache_note
(string note_name, string [note_value]);apache_note() is an Apache-specific function which gets and sets values in a request's notes table. If called with one argument, it returns the current value of note note_name. If called with two arguments, it sets the value of note note_name to note_value and returns the previous value of note note_name.
array getallheaders
(void);This function returns an associative array of all the HTTP headers in the current request.
Note: You can also get at the value of the common CGI variables by reading them from the environment, which works whether or not you are using PHP as an Apache module. Use phpinfo() to see a list of all of the environment variables defined this way.
Example 1. getallheaders() Example $headers = getallheaders(); while (list($header, $value) = each($headers)) { echo "$header: $value<br>\n"; } |
Note: getallheaders() is currently only supported when PHP runs as an Apache module.
int virtual
(string filename);virtual() is an Apache-specific function which is equivalent to <!--#include virtual...--> in mod_include. It performs an Apache sub-request. It is useful for including CGI scripts or .shtml files, or anything else that you would parse through Apache. Note that for a CGI script, the script must generate valid CGI headers. At the minimum that means it must generate a Content-type header. For PHP files, you should use include() or require().
array array
(...);Returns an array of the parameters. The parameters can be given an index with the => operator.
Note: array() is a language construct used to represent literal arrays, and not a regular function.
The following example demonstrates how to create a two-dimensional array, how to specify keys for associative arrays, and how to skip-and-continue numeric indices in normal arrays.
Example 1. array() example $fruits = array( "fruits" => array("a"=>"orange","b"=>"banana","c"=>"apple"), "numbers" => array(1, 2, 3, 4, 5, 6), "holes" => array("first", 5 => "second", "third") ); |
See also: list().
int array_push
(array array, mixed var, [...]);array_push() treats array as a stack, and pushes the passed variables onto the end of array. The length of array increases by the number of variables pushed. Has the same effect as:
$array[] = $var;repeated for each var.
Returns the new number of elements in the array.
Example 1. array_push() example $stack = array(1, 2); array_push($stack, "+", 3); |
See also array_pop(), array_shift(), and array_unshift().
Note: This function was added in PHP 4.0.
mixed array_pop
(array array);array_pop() pops and returns the last value of the array, shortening the array by one element.
Example 1. array_pop() example $stack = array("orange", "apple", "raspberry"); $fruit = array_pop($stack); After this, $stack has only 2 elements: "orange" and "apple", and $fruit has "raspberry". |
See also array_push(), array_shift(), and array_unshift().
Note: This function was added in PHP 4.0.
int array_unshift
(array array, mixed var, [...]);
array_unshift() prepends passed elements to the front of the array. Note that the list of elements is prepended as a whole, so that the prepended elements stay in the same order.
Returns the new number of elements in the array.
Example 1. array_unshift() example $queue = array("p1", "p3"); array_unshift($queue, "p4", "p5", "p6"); |
See also array_shift(), array_push(), and array_pop().
Note: This function was added in PHP 4.0.
mixed array_shift
(array array);array_shift() shifts the first value of the array off and returns it, shortening the array by one element and moving everything down.
Example 1. array_shift() example $args = array("-v", "-f"); $opt = array_shift($args); |
See also array_unshift(), array_push(), and array_pop().
Note: This function was added in PHP 4.0.
array array_slice
(array array, int offset, int
[length]
);array_slice() returns a sequence of elements from the array specified by the offset and length parameters.
If offset is positive, the sequence will start at that offset in the array. If offset is negative, the sequence will start that far from the end of the array.
If length is given and is positive, then the sequence will have that many elements in it. If length is given and is negative then the sequence will stop that many elements from the end of the array. If it is omitted, then the sequence will have everything from offset up until the end of the array.
Example 1. array_slice() examples $input = array("a", "b", "c", "d", "e"); $output = array_slice($input, 2); // returns "c", "d", and "e" $output = array_slice($input, 2, -1); // returns "c", "d" $output = array_slice($input, -2, 1); // returns "d" $output = array_slice($input, 0, 3); // returns "a", "b", and "c" |
See also array_splice().
Note: This function was added in PHP 4.0.
array array_splice
(array input, int offset, int
[length]
, array
[replacement]);array_splice() removed the elements designated by offset and length from the input array, and replaces them with the elements of the replacement array, if supplied.
If offset is positive then the start of removed portion is at that offset from the beginning of the input array. If offset is negative then it starts that far from the end of the input array.
If length is omitted, removes everything from offset to the end of the array. If length is specified and is positive, then that many elements will be removed. If length is specified and is negative then the end of the removed portion will be that many elements from the end of the array. Tip: to remove everything from offset to the end of the array when replacement is also specified, use count($input) for length.
If replacement array is specified, then the removed elements are replaced with elements from this array. If offset and length are such that nothing is removed, then the elements from the replacement array are inserted in the place specified by the offset. Tip: if the replacement is just one element it is not necessary to put array() around it, unless the element is an array itself.
The following equivalences hold:
array_push($input, $x, $y) array_splice($input, count($input), 0, array($x, $y)) array_pop($input) array_splice($input, -1) array_shift($input) array_splice($input, 0, 1) array_unshift($input, $x, $y) array_splice($input, 0, 0, array($x, $y)) $a[$x] = $y array_splice($input, $x, 1, $y)
Returns the array consisting of removed elements.
Example 1. array_splice() examples $input = array("red", "green", "blue", "yellow"); array_splice($input, 2); // $input is now array("red", "green") array_splice($input, 1, -1); // $input is now array("red", "yellow") array_splice($input, 1, count($input), "orange"); // $input is now array("red", "orange") array_splice($input, -1, 1, array("black", "maroon")); // $input is now array("red", "green", "blue", "black", "maroon") |
See also array_slice().
Note: This function was added in PHP 4.0.
array array_merge
(array array1, array array2, [ ...]
);array_merge() merges the elements of two or more arrays together so that the values of one are appended to the end of the previous one. It returns the resulting array.
If the input arrays had the same string keys, then the later value for that key will overwrite previous one. If, however, the arrays have the same numeric key, this does not happen since the values are appended.
Example 1. array_merge() example $array1 = array("color" => "red", 2, 4); $array2 = array("a", "b", "color" => "green", "shape" => "trapezoid"); array_merge($array1, $array2); Resulting array will be array("color" => "green", 2, 4, "a", "b", "shape" => "trapezoid"). |
Note: This function was added in PHP 4.0.
array array_keys
(array input);array_keys() returns all the keys, numeric and string, from the input array.
Example 1. array_keys() example $array = array(0 => 100, "color" => "red"); array_keys($array); // returns array(0, "color") |
See also array_values().
Note: This function was added in PHP 4.0.
array array_values
(array input);array_values() returns all the values from the input array.
Example 1. array_values() example $array = array("size" => "XL", "color" => "gold"); array_values($array); // returns array("XL", "gold") |
Note: This function was added in PHP 4.0.
int array_walk
(array arr, string func, mixed userdata);Applies the function named by func to each element of arr. func will be passed array value as the first parameter and array key as the second parameter. If userdata is supplied, it will be passed as the third parameter to the user function. If func requires more than two or three arguments, depending on userdata, a warning will be generated each time array_walk() calls func. These warnings may be suppressed by prepending the '@' sign to the array_walk() call, or by using error_reporting().
Note: If func needs to be working with the actual values of the array, specify that the first parameter of func should be passed by reference. Then any changes made to those elements will be made in the array itself.
Example 1. array_walk() example $fruits = array("d"=>"lemon","a"=>"orange","b"=>"banana","c"=>"apple"); function test_alter( &$item1, $key, $prefix ) { $item1 = "$prefix: $item1"; } function test_print( $item2, $key ) { echo "$key. $item2<br>\n"; } array_walk( $fruits, 'test_print' ); array_walk( $fruits, 'test_alter', 'fruit' ); array_walk( $fruits, 'test_print' ); |
void arsort
(array array);This function sorts an array such that array indices maintain their correlation with the array elements they are associated with. This is used mainly when sorting associative arrays where the actual element order is significant.
Example 1. arsort() example $fruits = array("d"=>"lemon","a"=>"orange","b"=>"banana","c"=>"apple"); arsort($fruits); for(reset($fruits); $key = key($fruits); next($fruits)) { echo "fruits[$key] = ".$fruits[$key]."\n"; } |
void asort
(array array);This function sorts an array such that array indices maintain their correlation with the array elements they are associated with. This is used mainly when sorting associative arrays where the actual element order is significant.
Example 1. asort() example $fruits = array("d"=>"lemon","a"=>"orange","b"=>"banana","c"=>"apple"); asort($fruits); for(reset($fruits); $key = key($fruits); next($fruits)) { echo "fruits[$key] = ".$fruits[$key]."\n"; } |
array compact
(string varname | array
varnames, [...]);compact() takes a variable number of parameters. Each parameter can be either a string containing the name of the variable, or an array of variable names. The array can contain other arrays of variable names inside it; compact() handles it recursively.
For each of these, compact() looks for a variable with that name in the current symbol table and adds it to the output array such that the variable name becomes the key and the contents of the variable become the value for that key. In short, it does the opposite of extract(). It returns the output array with all the variables added to it.
Example 1. compact() example $city = "San Francisco"; $state = "CA"; $event = "SIGGRAPH"; $location_vars = array("city", "state"); $result = compact("event", $location_vars); After this, $result will be array("event" => "SIGGRAPH", "city" => "San Francisco", "state" => "CA"). |
See also extract().
Note: This function was added in PHP 4.0.
int count
(mixed var);Returns the number of elements in var, which is typically an array (since anything else will have one element).
Returns 1 if the variable is not an array.
Returns 0 if the variable is not set.
Warning |
count() may return 0 for a variable that isn't set, but it may also return 0 for a variable that has been initialized with an empty array. Use isset() to test if a variable is set. |
See also: sizeof(), isset(), and is_array().
mixed current
(array array);Every array has an internal pointer to its "current" element, which is initialized to the first element inserted into the array.
The current() function simply returns the array element that's currently being pointed by the internal pointer. It does not move the pointer in any way. If the internal pointer points beyond the end of the elements list, current() returns false.
Warning |
If the array contains empty elements (0 or "", the empty string) then this function will return false for these elements as well. This makes it impossible to determine if you are really at the end of the list in such an array using current(). To properly traverse an array that may contain empty elements, use the each() function. |
array each
(array array);Returns the current key and value pair from the array array and advances the array cursor. This pair is returned in a four-element array, with the keys 0, 1, key, and value. Elements 0 and key contain the key name of the array element, and 1 and value contain the data.
If the internal pointer for the array points past the end of the array contents, each() returns false.
Example 1. each() examples $foo = array( "bob", "fred", "jussi", "jouni" ); $bar = each( $foo ); $bar now contains the following key/value pairs:
$foo = array( "Robert" => "Bob", "Seppo" => "Sepi" ); $bar = each( $foo ); $bar now contains the following key/value pairs:
|
each() is typically used in conjunction with list() to traverse an array; for instance, $HTTP_POST_VARS:
Example 2. Traversing $HTTP_POST_VARS with each() echo "Values submitted via POST method:<br>"; while (list($key, $val) = each($HTTP_POST_VARS)) { echo "$key => $val<br>"; } |
After each() has executed, the array cursor will be left on the next element of the array, or on the last element if it hits the end of the array.
See also key(), list(), current(), reset(), next(), and prev().
void extract
(array var_array, int [extract_type], string [prefix]);This function is used to import variables from an array into the current symbol table. It takes associative array var_array and treats keys as variable names and values as variable values. For each key/value pair it will create a variable in the current symbol table, subject to extract_type and prefix parameters.
extract() checks for colissions with existing variables. The way collisions are treated is determined by extract_type. It can be one of the following values:
If there is a collision, overwrite the existing variable.
If there is a collision, don't overwrite the existing variable.
If there is a collision, prefix the new variable with prefix.
Prefix all variables with prefix.
If extract_type is not specified, it is assumed to be EXTR_OVERWRITE.
Note that prefix is only required if extract_type is EXTR_PREFIX_SAME or EXTR_PREFIX_ALL.
extract() checks each key to see if it constitues a valid variable name, and if it does only then does it proceed to import it.
A possible use for extract is to import into symbol table variables contained in an associative array returned by wddx_deserialize().
Example 1. extract example <? /* Suppose that $var_array is an array returned from wddx_deserialize */ $size = "large"; $var_array = array("color" => "blue", "size" => "medium", "shape" => "sphere"); extract($var_array, EXTR_PREFIX_SAME, "wddx"); print "$color, $size, $shape, $wddx_size\n"; ?> |
The above example will produce:
blue, large, sphere, medium
The $size wasn't overwritten, becaus we specified EXTR_PREFIX_SAME, which resulted in $wddx_size being created. If EXTR_SKIP was specified, then $wddx_size wouldn't even have been created. EXTR_OVERWRITE would have cause $size to have value "medium", and EXTR_PREFIX_ALL would result in new variables being named $wddx_color, $wddx_size, and $wddx_shape.
bool in_array
(mixed needle, array haystack);Searches haystack for needle and returns true if it is found in the array, false otherwise.
Example 1. in_array() example $os = array("Mac", "NT", "Irix", "Linux"); if (in_array("Irix", $os)) print "Got Irix"; |
Note: This function was added in PHP 4.0.
int ksort
(array array);Sorts an array by key, maintaining key to data correlations. This is useful mainly for associative arrays.
Example 1. ksort() example $fruits = array("d"=>"lemon","a"=>"orange","b"=>"banana","c"=>"apple"); ksort($fruits); for(reset($fruits); $key = key($fruits); next($fruits)) { echo "fruits[$key] = ".$fruits[$key]."\n"; } |
void list
(...);Like array(), this is not really a function, but a language construct. list() is used to assign a list of variables in one operation.
Example 1. list() example <table> <tr> <th>Employee name</th> <th>Salary</th> </tr> <?php $result = mysql($conn, "SELECT id, name, salary FROM employees"); while (list($id, $name, $salary) = mysql_fetch_row($result)) { print(" <tr>\n". " <td><a href=\"info.php3?id=$id\">$name</a></td>\n". " <td>$salary</td>\n". " </tr>\n"); } ?></table> |
mixed next
(array array);Returns the array element in the next place that's pointed by the internal array pointer, or false if there are no more elements.
next() behaves like current(), with one difference. It advances the internal array pointer one place forward before returning the element. That means it returns the next array element and advances the internal array pointer by one. If advancing the internal array pointer results in going beyond the end of the element list, next() returns false.
Warning |
If the array contains empty elements then this function will return false for these elements as well. To properly traverse an array which may contain empty elements see the each() function. |
mixed prev
(array array);Returns the array element in the previous place that's pointed by the internal array pointer, or false if there are no more elements.
Warning |
If the array contains empty elements then this function will return false for these elements as well. To properly traverse an array which may contain empty elements see the each() function. |
prev() behaves just like next(), except it rewinds the internal array pointer one place instead of advancing it.
array range
(int low, int high);range() returns an array of integers from low to high, inclusive.
See shuffle() for an example of its use.
mixed reset
(array array);reset() rewinds array's internal pointer to the first element.
reset() returns the value of the first array element.
void rsort
(array array);This function sorts an array in reverse order (highest to lowest).
Example 1. rsort() example $fruits = array("lemon","orange","banana","apple"); rsort($fruits); for (reset($fruits); list($key,$value) = each($fruits); ) { echo "fruits[$key] = ", $value, "\n"; } |
void shuffle
(array array);This function shuffles (randomizes the order of the elements in) an array.
Example 1. shuffle() example $numbers = range(1,20); srand(time()); shuffle($numbers); while (list(,$number) = each($numbers)) { echo "$number "; } |
See also arsort(), asort(), ksort(), rsort(), sort() and usort().
void sort
(array array);This function sorts an array. Elements will be arranged from lowest to highest when this function has completed.
Example 1. sort() example $fruits = array("lemon","orange","banana","apple"); sort($fruits); for(reset($fruits); $key = key($fruits); next($fruits)) { echo "fruits[$key] = ".$fruits[$key]."\n"; } |
void uasort
(array array, function cmp_function);This function sorts an array such that array indices maintain their correlation with the array elements they are associated with. This is used mainly when sorting associative arrays where the actual element order is significant. The comparison function is user-defined.
void uksort
(array array, function cmp_function);This function will sort the keys of an array using a user-supplied comparison function. If the array you wish to sort needs to be sorted by some non-trivial criteria, you should use this function.
Example 1. uksort() example function mycompare($a, $b) { if ($a == $b) return 0; return ($a > $b) ? -1 : 1; } $a = array(4 => "four", 3 => "three", 20 => "twenty", 10 => "ten"); uksort($a, mycompare); while(list($key, $value) = each($a)) { echo "$key: $value\n"; } |
See also arsort(), asort(), uasort(), ksort(), rsort() and sort().
void usort
(array array, function cmp_function);This function will sort an array by its values using a user-supplied comparison function. If the array you wish to sort needs to be sorted by some non-trivial criteria, you should use this function.
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second. If two members compare as equal, their order in the sorted array is undefined.
Example 1. usort() example function cmp($a,$b) { if ($a == $b) return 0; return ($a > $b) ? -1 : 1; } $a = array(3,2,5,6,1); usort($a, cmp); while(list($key,$value) = each($a)) { echo "$key: $value\n"; } |
Note: Obviously in this trivial case the rsort() function would be more appropriate.
Warning |
The underlying quicksort function in some C libraries (such as on Solaris systems) may cause PHP to crash if the comparison function does not return consistent values. |
The aspell() functions allows you to check the spelling on a word and offer suggestions.
You need the aspell library, available from: http://metalab.unc.edu/kevina/aspell/
int aspell_new
(string master, string personal);aspell_new() opens up a new dictionary and returns the dictionary link identifier for use in other aspell functions.
Example 1. aspell_new $aspell_link=aspell_new("english"); |
boolean aspell_check
(int dictionary_link, string word);aspell_check() checks the spelling of a word and returns true if the spelling is correct, false if not.
Example 1. aspell_check $aspell_link=aspell_new("english"); if (aspell_check($aspell_link,"testt")) { echo "This is a valid spelling"; } else { echo "Sorry, wrong spelling"; } |
boolean aspell_check_raw
(int dictionary_link, string word);aspell_check_raw() checks the spelling of a word, without changing its case or trying to trim it in any way and returns true if the spelling is correct, false if not.
Example 1. aspell_check_raw $aspell_link=aspell_new("english"); if (aspell_check_raw($aspell_link,"testt")) { echo "This is a valid spelling"; } else { echo "Sorry, wrong spelling"; } |
array aspell_suggest
(int dictionary_link, string word);aspell_suggest() returns an array of possible spellings for the given word.
Example 1. aspell_suggest $aspell_link=aspell_new("english"); if (!aspell_check($aspell_link,"testt")) { $suggestions=aspell_suggest($aspell_link,"testt"); for($i=0; $i < count($suggestions); $i++) { echo "Possible spelling: " . $suggestions[$i] . "<br>"; } } |
string bcadd
(string left operand, string right operand, int [scale]);Adds the left operand to the right operand and returns the sum in a string. The optional scale parameter is used to set the number of digits after the decimal place in the result.
See also bcsub().
int bccomp
(string left operand, string right operand, int [scale]);Compares the left operand to the right operand and returns the result as an integer. The optional scale parameter is used to set the number of digits after the decimal place which will be used in the comparion. The return value is 0 if the two operands are equal. If the left operand is larger than the right operand the return value is +1 and if the left operand is less than the right operand the return value is -1.
string bcdiv
(string left operand, string right operand, int [scale]);Divides the left operand by the right operand and returns the result. The optional scale sets the number of digits after the decimal place in the result.
See also bcmul().
string bcmod
(string left operand, string modulus);Get the modulus of the left operand using modulus.
See also bcdiv().
string bcmul
(string left operand, string right operand, int [scale]);Multiply the left operand by the right operand and returns the result. The optional scale sets the number of digits after the decimal place in the result.
See also bcdiv().
string bcpow
(string x, string y, int [scale]);Raise x to the power y. The scale can be used to set the number of digits after the decimal place in the result.
See also bcsqrt().
string bcscale
(int scale);This function sets the default scale parameter for all subsequent bc math functions that do not explicitly specify a scale parameter.
string bcsqrt
(string operand, int scale);Return the square root of the operand. The optional scale parameter sets the number of digits after the decimal place in the result.
See also bcpow().
string bcsub
(string left operand, string right operand, int [scale]);Subtracts the right operand from the left operand and returns the result in a string. The optional scale parameter is used to set the number of digits after the decimal place in the result.
See also bcadd().
The calendar functions are only available if you have compiled the calendar extension in dl/calendar. Read dl/README for instructions on using it.
The calendar extension presents a series of functions to simplify converting between different calendar formats. The intermediary or standard it is based on is the Julian Day Count. The Julian Day Count is a count of days starting way earlier than any date most people would need to track (somewhere around 4000bc). To convert between calendar systems, you must first convert to Julian Day Count, then to the calendar system of your choice. Julian Day Count is very different from the Julian Calendar! For more information on calendar systems visit http://genealogy.org/~scottlee/cal-overview.html. Excerpts from this page are included in these instructions, and are in quotes.
string jdtogregorian
(int julianday);Converts Julian Day Count to a string containing the Gregorian date in the format of "month/day/year"
int gregoriantojd
(int month, int day, int year);Valid Range for Gregorian Calendar 4714 B.C. to 9999 A.D.
Although this software can handle dates all the way back to 4714 B.C., such use may not be meaningful. The Gregorian calendar was not instituted until October 15, 1582 (or October 5, 1582 in the Julian calendar). Some countries did not accept it until much later. For example, Britain converted in 1752, The USSR in 1918 and Greece in 1923. Most European countries used the Julian calendar prior to the Gregorian.
Example 1. Calendar functions <?php $jd = GregorianToJD(10,11,1970); echo("$jd\n"); $gregorian = JDToGregorian($jd); echo("$gregorian\n"); ?> |
string jdtojulian
(int julianday);Converts Julian Day Count to a string containing the Julian Calendar Date in the format of "month/day/year".
int juliantojd
(int month, int day, int year);Valid Range for Julian Calendar 4713 B.C. to 9999 A.D.
Although this software can handle dates all the way back to 4713 B.C., such use may not be meaningful. The calendar was created in 46 B.C., but the details did not stabilize until at least 8 A.D., and perhaps as late at the 4th century. Also, the beginning of a year varied from one culture to another - not all accepted January as the first month.
int jewishtojd
(int month, int day, int year);Valid Range Although this software can handle dates all the way back to the year 1 (3761 B.C.), such use may not be meaningful.
The Jewish calendar has been in use for several thousand years, but in the early days there was no formula to determine the start of a month. A new month was started when the new moon was first observed.
string jdtofrench
(int month, int day, int year);Converts a Julian Day Count to the French Republican Calendar.
int frenchtojd
(int month, int day, int year);Converts a date from the French Republican Calendar to a Julian Day Count
These routines only convert dates in years 1 through 14 (Gregorian dates 22 September 1792 through 22 September 1806). This more than covers the period when the calendar was in use.
string jdmonthname
(int julianday, int mode);Returns a string containing a month name. mode tells this function which calendar to convert the Julian Day Count to, and what type of month names are to be returned.
Table 1. Calendar modes
Mode | Meaning |
---|---|
0 | Gregorian - apreviated |
1 | Gregorian |
2 | Julian - apreviated |
3 | Julian |
4 | Jewish |
5 | French Republican |
mixed jddayofweek
(int julianday, int mode);Returns the day of the week. Can return a string or an int depending on the mode.
Table 1. Calendar week modes
Mode | Meaning |
---|---|
0 | returns the day number as an int (0=sunday, 1=monday, etc) |
1 | returns string containing the day of week (english-gregorian) |
2 | returns a string containing the abreviated day of week (english-gregorian) |
int easter_date
(int year);Returns the UNIX timestamp corresponding to midnight on Easter of the given year. If no year is specified, the current year is assumed.
Warning: This function will generate a warning if the year is outside of the range for UNIX timestamps (i.e. before 1970 or after 2037).
Example 1. easter_date() example echo date( "M-d-Y", easter_date(1999) ); /* "Apr-04-1999" */ echo date( "M-d-Y", easter_date(2000) ); /* "Apr-23-2000" */ echo date( "M-d-Y", easter_date(2001) ); /* "Apr-15-2001" */ |
The date of Easter Day was defined by the Council of Nicaea in AD325 as the Sunday after the first full moon which falls on or after the Spring Equinox. The Equinox is assumed to always fall on 21st March, so the calculation reduces to determining the date of the full moon and the date of the following Sunday. The algorithm used here was introduced around the year 532 by Dionysius Exiguus. Under the Julian Calendar (for years before 1753) a simple 19-year cycle is used to track the phases of the Moon. Under the Gregorian Calendar (for years after 1753 - devised by Clavius and Lilius, and introduced by Pope Gregory XIII in October 1582, and into Britain and its then colonies in September 1752) two correction factors are added to make the cycle more accurate.
(The code is based on a C program by Simon Kershaw, <webmaster@ely.anglican.org>)
See easter_days() for calculating Easter before 1970 or after 2037.
int easter_days
(int year);Returns the number of days after March 21 on which Easter falls for a given year. If no year is specified, the current year is assumed.
This function can be used instead of easter_date() to calculate Easter for years which fall outside the range of UNIX timestamps (i.e. before 1970 or after 2037).
Example 1. easter_date() example echo easter_days(1999); /* 14, i.e. April 4 */ echo easter_days(1492); /* 32, i.e. April 22 */ echo easter_days(1913); /* 2, i.e. March 23 */ |
The date of Easter Day was defined by the Council of Nicaea in AD325 as the Sunday after the first full moon which falls on or after the Spring Equinox. The Equinox is assumed to always fall on 21st March, so the calculation reduces to determining the date of the full moon and the date of the following Sunday. The algorithm used here was introduced around the year 532 by Dionysius Exiguus. Under the Julian Calendar (for years before 1753) a simple 19-year cycle is used to track the phases of the Moon. Under the Gregorian Calendar (for years after 1753 - devised by Clavius and Lilius, and introduced by Pope Gregory XIII in October 1582, and into Britain and its then colonies in September 1752) two correction factors are added to make the cycle more accurate.
(The code is based on a C program by Simon Kershaw, <webmaster@ely.anglican.org>)
See also easter_date().
ClibPDF allows to create pdf documents with PHP. It is available at FastIO but is not free software. You should definitely read the licence before you start playing with ClibPDF. If you cannot fullfil the licence agreement consider using pdflib by Thomas Merz, which is also very powerful. ClibPDF functionality and API is similar to Thomas Merz pdflib but ClibPDF is, according to FastIO, faster and creates smaller documents. This may have changed with the new version 2.0 of pdflib. A simple benchmark (the pdfclock.c example from pdflib 2.0 turned into a php script) actually show no difference in speed at all. The file size is also similar if compression is turned off.
This documentation should be read with the ClibPDF manual since it explains much of the library in much more detail. Once you understand the manual of ClibPDF you should be able to start using the library with PHP.
Many functions in the native ClibPDF and the PHP module, as well as in pdflib, have the same name. All functions except for cpdf_open() take as their first parameter the handle for the document on which the function is to be performed. Currently this handle is not used internally since ClibPDF does not support the creation of several PDF documents at the same time. Actually, you should not even try it, the results are unpredictable. I cannot oversee what the consequences in a multi threaded environment are. According to the author of ClibPDF this will change in one of the next releases (current version when this was written is 1.10). If you need this functionality use the pdflib module.
One big advantage of ClibPDF over pdflib is the possibility to create the pdf document completely in memory without using temporary files. It also provides the ability to pass coordinates in a predefined unit length. This is a handy feature but can be simulated with pdf_translate().
Most of the functions are fairly easy to use. The most difficult part is probably creating a very simple PDF document at all. The following example should help you get started. It creates a document with one page. The page contains the text "Times-Roman" in an outlined 30pt font. The text is underlined.
Example 1. Simple ClibPDF Example <?php $cpdf = cpdf_open(0); cpdf_page_init($cpdf, 1, 0, 595, 842); cpdf_add_outline($cpdf, 0, 0, 0, 1, "Page 1"); cpdf_set_font($cpdf, "Times-Roman", 30, 4); cpdf_set_text_rendering($cpdf, 1); cpdf_text($cpdf, "Times Roman outlined", 50, 750); cpdf_moveto($cpdf, 50, 740); cpdf_lineto($cpdf, 330, 740); cpdf_stroke($cpdf); cpdf_finalize($cpdf); Header("Content-type: application/pdf"); cpdf_output_buffer($cpdf); cpdf_close($cpdf); ?> |
The pdflib distribution contains a more complex example which creates a series of pages with an analog clock. Here is that example converted into PHP using the ClibPDF extension:
Example 2. pdfclock example from pdflib 2.0 distribution <?php $radius = 200; $margin = 20; $pagecount = 40; $pdf = cpdf_open(0); cpdf_set_creator($pdf, "pdf_clock.php3"); cpdf_set_title($pdf, "Analog Clock"); while($pagecount-- > 0) { cpdf_page_init($pdf, $pagecount+1, 0, 2 * ($radius + $margin), 2 * ($radius + $margin), 1.0); cpdf_set_page_animation($pdf, 4, 0.5, 0, 0, 0); /* wipe */ cpdf_translate($pdf, $radius + $margin, $radius + $margin); cpdf_save($pdf); cpdf_setrgbcolor($pdf, 0.0, 0.0, 1.0); /* minute strokes */ cpdf_setlinewidth($pdf, 2.0); for ($alpha = 0; $alpha < 360; $alpha += 6) { cpdf_rotate($pdf, 6.0); cpdf_moveto($pdf, $radius, 0.0); cpdf_lineto($pdf, $radius-$margin/3, 0.0); cpdf_stroke($pdf); } cpdf_restore($pdf); cpdf_save($pdf); /* 5 minute strokes */ cpdf_setlinewidth($pdf, 3.0); for ($alpha = 0; $alpha < 360; $alpha += 30) { cpdf_rotate($pdf, 30.0); cpdf_moveto($pdf, $radius, 0.0); cpdf_lineto($pdf, $radius-$margin, 0.0); cpdf_stroke($pdf); } $ltime = getdate(); /* draw hour hand */ cpdf_save($pdf); cpdf_rotate($pdf, -(($ltime['minutes']/60.0) + $ltime['hours'] - 3.0) * 30.0); cpdf_moveto($pdf, -$radius/10, -$radius/20); cpdf_lineto($pdf, $radius/2, 0.0); cpdf_lineto($pdf, -$radius/10, $radius/20); cpdf_closepath($pdf); cpdf_fill($pdf); cpdf_restore($pdf); /* draw minute hand */ cpdf_save($pdf); cpdf_rotate($pdf, -(($ltime['seconds']/60.0) + $ltime['minutes'] - 15.0) * 6.0); cpdf_moveto($pdf, -$radius/10, -$radius/20); cpdf_lineto($pdf, $radius * 0.8, 0.0); cpdf_lineto($pdf, -$radius/10, $radius/20); cpdf_closepath($pdf); cpdf_fill($pdf); cpdf_restore($pdf); /* draw second hand */ cpdf_setrgbcolor($pdf, 1.0, 0.0, 0.0); cpdf_setlinewidth($pdf, 2); cpdf_save($pdf); cpdf_rotate($pdf, -(($ltime['seconds'] - 15.0) * 6.0)); cpdf_moveto($pdf, -$radius/5, 0.0); cpdf_lineto($pdf, $radius, 0.0); cpdf_stroke($pdf); cpdf_restore($pdf); /* draw little circle at center */ cpdf_circle($pdf, 0, 0, $radius/30); cpdf_fill($pdf); cpdf_restore($pdf); cpdf_finalize_page($pdf, $pagecount+1); } cpdf_finalize($pdf); Header("Content-type: application/pdf"); cpdf_output_buffer($pdf); cpdf_close($pdf); ?> |
void cpdf_set_creator
(string creator);The cpdf_set_creator() function sets the creator of a pdf document.
See also cpdf_set_subject(), cpdf_set_title(), cpdf_set_keywords().
void cpdf_set_title
(string title);The cpdf_set_title() function sets the title of a pdf document.
See also cpdf_set_subject(), cpdf_set_creator(), cpdf_set_keywords().
void cpdf_set_subject
(string subject);The cpdf_set_subject() function sets the subject of a pdf document.
See also cpdf_set_title(), cpdf_set_creator(), cpdf_set_keywords().
void cpdf_set_keywords
(string keywords);The cpdf_set_keywords() function sets the keywords of a pdf document.
See also cpdf_set_title(), cpdf_set_creator(), cpdf_set_subject().
int cpdf_open
(int compression, string filename);The cpdf_open() function opens a new pdf document. The first parameter turns document compression on if it is unequal to 0. The second optional parameter sets the file in which the document is written. If it is omitted the document is created in memory and can either be written into a file with the cpdf_save_to_file() or written to standard output with cpdf_output_buffer().
Note: The return value will be needed in futher versions of ClibPDF as the first parameter in all other functions which are writing to the pdf document.
The ClibPDF library takes the filename "-" as a synonym for stdout. If PHP is compiled as an apache module this will not work because the way ClibPDF outputs to stdout does not work with apache. You can solve this problem by skipping the filename and using cpdf_output_buffer() to output the pdf document.
See also cpdf_close(), cpdf_output_buffer().
void cpdf_close
(int pdf document);The cpdf_close() function closes the pdf document. This should be the last function even after cpdf_finalize(), cpdf_output_buffer() and cpdf_save_to_file().
See also cpdf_open().
void cpdf_page_init
(int pdf document, int page number, int orientation, double height, double width, double unit);The cpdf_page_init() function starts a new page with height height and width width. The page has number page number and orientation orientation. orientation can be 0 for portrait and 1 for landscape. The last optional parameter unit sets the unit for the koordinate system. The value should be the number of postscript points per unit. Since one inch is equal to 72 points, a value of 72 would set the unit to one inch. The default is also 72.
See also cpdf_set_current_page().
void cpdf_finalize_page
(int pdf document, int page number);The cpdf_finalize_page() function ends the page with page number page number. This function is only for saving memory. A finalized page takes less memory but cannot be modified anymore.
See also cpdf_page_init().
void cpdf_finalize
(int pdf document);The cpdf_finalize() function ends the document. You still have to call cpdf_close().
See also cpdf_close().
void cpdf_output_buffer
(int pdf document);The cpdf_output_buffer() function outputs the pdf document to stdout. The document has to be created in memory which is the case if cpdf_open() has been called with no filename parameter.
See also cpdf_open().
void cpdf_save_to_file
(int pdf document, string filename);The cpdf_save_to_file() function outputs the pdf document into a file if it has been created in memory. This function is not needed if the pdf document has been open by specifying a filename as a parameter of cpdf_open().
See also cpdf_output_buffer(), cpdf_open().
void cpdf_set_current_page
(int pdf document, int page number);The cpdf_set_current_page() function set the page on which all operations are performed. One can switch between pages until a page is finished with cpdf_finalize_page().
See also cpdf_finalize_page().
void cpdf_begin_text
(int pdf document);The cpdf_begin_text() function starts a text section. It must be ended with cpdf_end_text().
Example 1. Text output <?php cpdf_begin_text($pdf); cpdf_set_font($pdf, 16, "Helvetica", 4); cpdf_text($pdf, 100, 100, "Some text"); cpdf_end_text($pdf) ?> |
See also cpdf_end_text().
void cpdf_end_text
(int pdf document);The cpdf_end_text() function ends a text section which was started with cpdf_begin_text().
Example 1. Text output <?php cpdf_begin_text($pdf); cpdf_set_font($pdf, 16, "Helvetica", 4); cpdf_text($pdf, 100, 100, "Some text"); cpdf_end_text($pdf) ?> |
See also cpdf_begin_text().
void cpdf_show
(int pdf document, string text);The cpdf_show() function outputs the string in text at the current position.
See also cpdf_text(), cpdf_begin_text(), cpdf_end_text().
void cpdf_show_xy
(int pdf document, string text, double x-koor, double y-koor, int mode);The cpdf_show_xy() function outputs the string text at position with coordinates (x-koor, y-koor). The last optional parameter determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit.
Note: The function cpdf_show_xy() is identical to cpdf_text() without the optional parameters.
See also cpdf_text().
void cpdf_text
(int pdf document, string text, double x-koor, double y-koor, int mode, double orientation, int alignmode);The cpdf_text() function outputs the string text at position with coordinates (x-koor, y-koor). The optional parameter determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit. The optional parameter orientation is the rotation of the text in degree. The optional parameter alignmode determines how the text is align. See the ClibPDF documentation for possible values.
See also cpdf_show_xy().
void cpdf_set_font
(int pdf document, string font name, double size, int encoding);The cpdf_set_font() function sets the the current font face, font size and encoding. Currently only the standard postscript fonts are supported. The last parameter encoding can take the following values: 2 = macroman, 3 = macexpert, 4 = winansi. Any other value selects the font's buildin encoding.
void cpdf_set leading
(int pdf document, double distance);The cpdf_set_leading() function sets the distance between text lines. This will be used if text is output by cpdf_continue_text().
See also cpdf_continue_text().
void cpdf_set_text_rendering
(int pdf document, int mode);The cpdf_set_text_rendering() function determines how text is rendered. The possible values for mode are 0=fill text, 1=stroke text, 2=fill and stroke text, 3=invisible, 4=fill text and add it to cliping path, 5=stroke text and add it to clipping path, 6=fill and stroke text and add it to cliping path, 7=add it to clipping path.
void cpdf_set_horiz_scaling
(int pdf document, double scale);The cpdf_set_horiz_scaling() function sets the horizontal scaling to scale percent.
void cpdf_set_text_rise
(int pdf document, double value);The cpdf_set_text_rise() function sets the text rising to value units.
void cpdf_set_text_matrix
(int pdf document, array matrix);The cpdf_set_text_matrix() function sets a matrix which describes a transformation applied on the current text font.
void cpdf_set_text_pos
(int pdf document, double x-koor, double y-koor, int mode);The cpdf_set_text_pos() function sets the position of text for the next cpdf_show() function call.
The last optional parameter mode determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit.
See also cpdf_show(), cpdf_text().
void cpdf_set_char_spacing
(int pdf document, double space);The cpdf_set_char_spacing() function sets the spacing between characters.
See also cpdf_set_word_spacing(), cpdf_set_leading().
void cpdf_set_word_spacing
(int pdf document, double space);The cpdf_set_word_spacing() function sets the spacing between words.
See also cpdf_set_char_spacing(), cpdf_set_leading().
void cpdf_continue_text
(int pdf document, string text);The cpdf_continue_text() function outputs the string in text in the next line.
See also cpdf_show_xy(), cpdf_text(), cpdf_set_leading(), cpdf_set_text_pos().
double cpdf_stringwidth
(int pdf document, string text);The cpdf_stringwidth() function returns the width of the string in text. It requires a font to be set before.
See also cpdf_set_font().
void cpdf_save
(int pdf document);The cpdf_save() function saves the current enviroment. It works like the postscript command gsave. Very useful if you want to translate or rotate an object without effecting other objects.
See also cpdf_restore().
void cpdf_restore
(int pdf document);The cpdf_restore() function restores the enviroment saved with cpdf_save(). It works like the postscript command grestore. Very useful if you want to translate or rotate an object without effecting other objects.
Example 1. Save/Restore <?php cpdf_save($pdf); // do all kinds of rotations, transformations, ... cpdf_restore($pdf) ?> |
See also cpdf_save().
void cpdf_translate
(int pdf document, double x-koor, double y-koor, int mode);The cpdf_translate() function set the origin of coordinate system to the point (x-koor, y-koor).
The last optional parameter determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit.
void cpdf_scale
(int pdf document, double x-scale, double y-scale);The cpdf_scale() function set the scaling factor in both directions.
void cpdf_rotate
(int pdf document, double angle);The cpdf_rotate() function set the rotation in degress to angle.
void cpdf_setflat
(int pdf document, double value);The cpdf_setflat() function set the flatness to a value between 0 and 100.
void cpdf_setlinejoin
(int pdf document, long value);The cpdf_setlinejoin() function set the linejoin parameter between a value of 0 and 2. 0 = miter, 1 = round, 2 = bevel.
void cpdf_setlinecap
(int pdf document, int value);The cpdf_setlinecap() function set the linecap parameter between a value of 0 and 2. 0 = butt end, 1 = round, 2 = projecting square.
void cpdf_setmiterlimit
(int pdf document, double value);The cpdf_setmiterlimit() function set the miter limit to a value greater or equal than 1.
void cpdf_setlinewidth
(int pdf document, double width);The cpdf_setlinewidth() function set the line width to width.
void cpdf_setdash
(int pdf document, double white, double black);The cpdf_setdash() function set the dash pattern white white units and black black units. If both are 0 a solid line is set.
void cpdf_moveto
(int pdf document, double x-koor, double y-koor, int mode);The cpdf_moveto() function set the current point to the coordinates x-koor and y-koor.
The last optional parameter determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit.
void cpdf_rmoveto
(int pdf document, double x-koor, double y-koor, int mode);The cpdf_rmoveto() function set the current point relative to the coordinates x-koor and y-koor.
The last optional parameter determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit.
See also cpdf_moveto().
void cpdf_curveto
(int pdf document, double x1, double y1, double x2, double y2, double x3, double y3, int mode);The cpdf_curveto() function draws a Bezier curve from the current point to the point (x3, y3) using (x1, y1) and (x2, y2) as control points.
The last optional parameter determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit.
See also cpdf_moveto(), cpdf_rmoveto(), cpdf_rlineto(), cpdf_lineto().
void cpdf_lineto
(int pdf document, double x-koor, double y-koor, int mode);The cpdf_lineto() function draws a line from the current point to the point with coordinates (x-koor, y-koor).
The last optional parameter determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit.
See also cpdf_moveto(), cpdf_rmoveto(), cpdf_curveto().
void cpdf_rlineto
(int pdf document, double x-koor, double y-koor, int mode);The cpdf_rlineto() function draws a line from the current point to the relative point with coordinates (x-koor, y-koor).
The last optional parameter determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit.
See also cpdf_moveto(), cpdf_rmoveto(), cpdf_curveto().
void cpdf_circle
(int pdf document, double x-koor, double y-koor, double radius, int mode);The cpdf_circle() function draws a circle with center at point (x-koor, y-koor) and radius radius.
The last optional parameter determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit.
See also cpdf_arc().
void cpdf_arc
(int pdf document, double x-koor, double y-koor, double radius, double start, double end, int mode);The cpdf_arc() function draws an arc with center at point (x-koor, y-koor) and radius radius, starting at angle start and ending at angle end.
The last optional parameter determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit.
See also cpdf_circle().
void cpdf_rect
(int pdf document, double x-koor, double y-koor, double width, double height, int mode);The cpdf_rect() function draws a rectangle with its lower left corner at point (x-koor, y-koor). This width is set to widgth. This height is set to height.
The last optional parameter determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit.
void cpdf_closepath
(int pdf document);The cpdf_closepath() function closes the current path.
void cpdf_stroke
(int pdf document);The cpdf_stroke() function draws a line along current path.
See also cpdf_closepath(), cpdf_closepath_stroke().
void cpdf_closepath_stroke
(int pdf document);The cpdf_closepath_stroke() function is a combination of cpdf_closepath() and cpdf_stroke(). Than clears the path.
See also cpdf_closepath(), cpdf_stroke().
void cpdf_fill
(int pdf document);The cpdf_fill() function fills the interior of the current path with the current fill color.
See also cpdf_closepath(), cpdf_stroke(), cpdf_setgray_fill(), cpdf_setgray(), cpdf_setrgbcolor_fill(), cpdf_setrgbcolor().
void cpdf_fill_stroke
(int pdf document);The cpdf_fill_stroke() function fills the interior of the current path with the current fill color and draws current path.
See also cpdf_closepath(), cpdf_stroke(), cpdf_fill(), cpdf_setgray_fill(), cpdf_setgray(), cpdf_setrgbcolor_fill(), cpdf_setrgbcolor().
void cpdf_closepath_fill_stroke
(int pdf document);The cpdf_closepath_fill_stroke() function closes, fills the interior of the current path with the current fill color and draws current path.
See also cpdf_closepath(), cpdf_stroke(), cpdf_fill(), cpdf_setgray_fill(), cpdf_setgray(), cpdf_setrgbcolor_fill(), cpdf_setrgbcolor().
void cpdf_clip
(int pdf document);The cpdf_clip() function clips all drawing to the current path.
void cpdf_setgray_fill
(int pdf document, double value);The cpdf_setgray_fill() function sets the current gray value to fill a path.
See also cpdf_setrgbcolor_fill().
void cpdf_setgray_stroke
(int pdf document, double gray value);The cpdf_setgray_stroke() function sets the current drawing color to the given gray value.
See also cpdf_setrgbcolor_stroke().
void cpdf_setgray
(int pdf document, double gray value);The cpdf_setgray_stroke() function sets the current drawing and filling color to the given gray value.
See also cpdf_setrgbcolor_stroke(), cpdf_setrgbcolor_fill().
void cpdf_setrgbcolor_fill
(int pdf document, double red value, double green value, double blue value);The cpdf_setrgbcolor_fill() function sets the current rgb color value to fill a path.
See also cpdf_setrgbcolor_stroke(), cpdf_setrgbcolor().
void cpdf_setrgbcolor_stroke
(int pdf document, double red value, double green value, double blue value);The cpdf_setrgbcolor_stroke() function sets the current drawing color to the given rgb color value.
See also cpdf_setrgbcolor_fill(), cpdf_setrgbcolor().
void cpdf_setrgbcolor
(int pdf document, double red value, double green value, double blue value);The cpdf_setrgbcolor_stroke() function sets the current drawing and filling color to the given rgb color value.
See also cpdf_setrgbcolor_stroke(), cpdf_setrgbcolor_fill().
void cpdf_add_outline
(int pdf document, string text);The cpdf_add_outline() function adds a bookmark with text text that points to the current page.
Example 1. Adding a page outline <?php $cpdf = cpdf_open(0); cpdf_page_init($cpdf, 1, 0, 595, 842); cpdf_add_outline($cpdf, 0, 0, 0, 1, "Page 1"); // ... // some drawing // ... cpdf_finalize($cpdf); Header("Content-type: application/pdf"); cpdf_output_buffer($cpdf); cpdf_close($cpdf); ?>
|
void cpdf_set_page_animation
(int pdf document, int transition, double duration);The cpdf_set_page_animation() function set the transition between following pages.
The value of transition can be
0 for none, |
1 for two lines sweeping across the screen reveal the page, |
2 for multiple lines sweeping across the screen reveal the page, |
3 for a box reveals the page, |
4 for a single line sweeping across the screen reveals the page, |
5 for the old page dissolves to reveal the page, |
6 for the dissolve effect moves from one screen edge to another, |
7 for the old page is simply replaced by the new page (default) |
The value of duration is the number of seconds between page flipping.
int cpdf_open_jpeg
(int pdf document, string file name, double x-koor, double y-koor, double angle, double width, double height, double x-scale, double y-scale, int mode);The cpdf_import_jpeg() function opens an image stored in the file with the name file name. The format of the image has to be jpeg. The image is placed on the current page at position (x-koor, y-koor). The image is rotated by angle degres.
The last optional parameter determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit.
See also cpdf_place_inline_image(),
void cpdf_place_inline_image
(int pdf document, int image, double x-koor, double y-koor, double angle, double width, double height, int mode);The cpdf_place_inline_image() function places an image created with the php image functions on the page at postion (x-koor, y-koor). The image can be scaled at the same time.
The last optional parameter determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit.
See also cpdf_import_jpeg(),
void cpdf_add_annotation
(int pdf document, double llx, double lly, double urx, double ury, string title, string content, int mode);The cpdf_add_annotation() adds a note with the lower left corner at (llx, lly) and the upper right corner at (urx, ury).
The last optional parameter determines the unit length. If is 0 or omitted the default unit as specified for the page is used. Otherwise the koodinates are measured in postscript points disregarding the current unit.
int checkdate
(int month, int day, int year);Returns true if the date given is valid; otherwise returns false. Checks the validity of the date formed by the arguments. A date is considered valid if:
year is between 0 and 32767 inclusive
month is between 1 and 12 inclusive
day is within the allowed number of days for the given month. Leap years are taken into consideration.
string date
(string format, int
[timestamp]
);Returns a string formatted according to the given format string using the given timestamp or the current local time if no timestamp is given.
The following characters are recognized in the format string:
a - "am" or "pm"
A - "AM" or "PM"
d - day of the month, 2 digits with leading zeros; i.e. "01" to "31"
D - day of the week, textual, 3 letters; i.e. "Fri"
F - month, textual, long; i.e. "January"
h - hour, 12-hour format; i.e. "01" to "12"
H - hour, 24-hour format; i.e. "00" to "23"
g - hour, 12-hour format without leading zeros; i.e. "1" to "12"
G - hour, 24-hour format without leading zeros; i.e. "0" to "23"
i - minutes; i.e. "00" to "59"
j - day of the month without leading zeros; i.e. "1" to "31"
l (lowercase 'L') - day of the week, textual, long; i.e. "Friday"
L - boolean for whether it is a leap year; i.e. "0" or "1"
m - month; i.e. "01" to "12"
n - month without leading zeros; i.e. "1" to "12"
M - month, textual, 3 letters; i.e. "Jan"
s - seconds; i.e. "00" to "59"
S - English ordinal suffix, textual, 2 characters; i.e. "th", "nd"
t - number of days in the given month; i.e. "28" to "31"
U - seconds since the epoch
w - day of the week, numeric, i.e. "0" (Sunday) to "6" (Saturday)
Y - year, 4 digits; i.e. "1999"
y - year, 2 digits; i.e. "99"
z - day of the year; i.e. "0" to "365"
Z - timezone offset in seconds (i.e. "-43200" to "43200")
Example 1. date() example print (date("l dS of F Y h:i:s A")); print ("July 1, 2000 is on a " . date("l", mktime(0,0,0,7,1,2000))); |
It is possible to use date() and mktime() together to find dates in the future or the past.
Example 2. date() and mktime() example $tomorrow = mktime(0,0,0,date("m") ,date("d")+1,date("Y")); $lastmonth = mktime(0,0,0,date("m")-1,date("d"), date("Y")); $nextyear = mktime(0,0,0,date("m"), date("d", date("Y")+1); |
To format dates in other languages, you should use the setlocale() and strftime() functions.
string strftime
(string format, int timestamp);Returns a string formatted according to the given format string using the given timestamp or the current local time if no timestamp is given. Month and weekday names and other language dependent strings respect the current locale set with setlocale().
The following conversion specifiers are recognized in the format string:
%a - abbreviated weekday name according to the current locale
%A - full weekday name according to the current locale
%b - abbreviated month name according to the current locale
%B - full month name according to the current locale
%c - preferred date and time representation for the current locale
%d - day of the month as a decimal number (range 00 to 31)
%H - hour as a decimal number using a 24-hour clock (range 00 to 23)
%I - hour as a decimal number using a 12-hour clock (range 01 to 12)
%j - day of the year as a decimal number (range 001 to 366)
%m - month as a decimal number (range 1 to 12)
%M - minute as a decimal number
%p - either `am' or `pm' according to the given time value, or the corresponding strings for the current locale
%S - second as a decimal number
%U - week number of the current year as a decimal number, starting with the first Sunday as the first day of the first week
%W - week number of the current year as a decimal number, starting with the first Monday as the first day of the first week
%w - day of the week as a decimal, Sunday being 0
%x - preferred date representation for the current locale without the time
%X - preferred time representation for the current locale without the date
%y - year as a decimal number without a century (range 00 to 99)
%Y - year as a decimal number including the century
%Z - time zone or name or abbreviation
%% - a literal `%' character
Example 1. strftime() example setlocale ("LC_TIME", "C"); print(strftime("%A in Finnish is ")); setlocale ("LC_TIME", "fi_FI"); print(strftime("%A, in French ")); setlocale ("LC_TIME", "fr_CA"); print(strftime("%A and in German ")); setlocale ("LC_TIME", "de_DE"); print(strftime("%A.\n")); |
See also setlocale() and mktime().
string gmstrftime
(string format, int timestamp);Behaves the same as strftime() except that the time returned is Greenwich Mean Time (GMT). For example, when run in Eastern Standard Time (GMT -0500), the first line below prints "Dec 31 1998 20:00:00", while the second prints "Jan 01 1999 01:00:00".
Example 1. gmstrftime() example setlocale ('LC_TIME','en_US'); echo strftime ("%b %d %Y %H:%M:%S",mktime(20,0,0,12,31,98))."\n"; echo gmstrftime ("%b %d %Y %H:%M:%S",mktime(20,0,0,12,31,98))."\n"; |
See also strftime().
array getdate
(int timestamp);Returns an associative array containing the date information of the timestamp as the following array elements:
"seconds" - seconds
"minutes" - minutes
"hours" - hours
"mday" - day of the month
"wday" - day of the week, numeric
"mon" - month, numeric
"year" - year, numeric
"yday" - day of the year, numeric; i.e. "299"
"weekday" - day of the week, textual, full; i.e. "Friday"
"month" - month, textual, full; i.e. "January"
array gettimeofday
(void);This is an interface to gettimeofday(2). It returns an associative array containing the data returned from the system call.
"sec" - seconds
"usec" - microseconds
"minuteswest" - minutes west of Greenwich
"dsttime" - type of dst correction
string gmdate
(string format, int timestamp);Identical to the date() function except that the time returned is Greenwich Mean Time (GMT). For example, when run in Finland (GMT +0200), the first line below prints "Jan 01 1998 00:00:00", while the second prints "Dec 31 1997 22:00:00".
Example 1. gmdate() example echo date( "M d Y H:i:s",mktime(0,0,0,1,1,1998) ); echo gmdate( "M d Y H:i:s",mktime(0,0,0,1,1,1998) ); |
See also date(), mktime() and gmmktime().
int mktime
(int hour, int minute, int second, int month, int day, int year, int [is_dst]);Warning: Note the strange order of arguments, which differs from the order of arguments in a regular UNIX mktime() call and which does not lend itself well to leaving out parameters from right to left (see below). It is a common error to mix these values up in a script.
Returns the Unix timestamp corresponding to the arguments given. This timestamp is a long integer containing the number of seconds between the Unix Epoch (January 1 1970) and the time specified.
Arguments may be left out in order from right to left; any arguments thus omitted will be set to the current value according to the local date and time.
is_dst can be set to 1 if the time is during daylight savings time, 0 if it is not, or -1 (the default) if it is unknown whether the time is within daylight savings time or not.
Note: is_dst was added in 3.0.10.
mktime() is useful for doing date arithmetic and validation, as it will automatically calculate the correct value for out-of-range input. For example, each of the following lines produces the string "Jan-01-1998".
Example 1. mktime() example echo date( "M-d-Y", mktime(0,0,0,12,32,1997) ); echo date( "M-d-Y", mktime(0,0,0,13,1,1997) ); echo date( "M-d-Y", mktime(0,0,0,1,1,1998) ); |
int gmmktime
(int hour, int minute, int second, int month, int day, int year, int [is_dst]);Identical to mktime() except the passed parameters represents a GMT date.
int time
(void);Returns the current time measured in the number of seconds since the Unix Epoch (January 1 1970 00:00:00 GMT).
See also date().
string microtime
(void);Returns the string "msec sec" where sec is the current time measured in the number of seconds since the Unix Epoch (0:00:00 January 1, 1970 GMT), and msec is the microseconds part. This function is only available on operating systems that support the gettimeofday() system call.
See also time().
These functions build the foundation for accessing Berkeley DB style databases.
This is a general abstraction layer for several file-based databases. As such, functionality is limited to a subset of features modern databases such as Sleepycat Software's DB2 support. (This is not to be confused with IBM's DB2 software, which is supported through the ODBC functions.)
The behaviour of various aspects depend on the implementation of the underlying database. Functions such as dba_optimize() and dba_sync() will do what they promise for one database and will do nothing for others.
The following handlers are supported:
dbm is the oldest (original) type of Berkeley DB style databases. You should avoid it, if possible. We do not support the compatibility functions built into DB2 and gdbm, because they are only compatible on the source code level, but cannot handle the original dbm format.
ndbm is a newer type and more flexible than dbm. It still has most of the arbitrary limits of dbm (therefore it is deprecated).
gdbm is the GNU database manager.
db2 is Sleepycat Software's DB2. It is described as "a programmatic toolkit that provides high-performance built-in database support for both standalone and client/server applications."
cdb is "a fast, reliable, lightweight package for creating and reading constant databases." It is from the author of qmail and can be found here. Since it is constant, we support only reading operations.
Example 1. DBA example <?php $id = dba_open("/tmp/test.db", "n", "db2"); if(!$id) { echo "dba_open failed\n"; exit; } dba_replace("key", "This is an example!", $id); if(dba_exists("key", $id)) { echo dba_fetch("key", $id); dba_delete("key", $id); } dba_close($id); ?> |
DBA is binary safe and does not have any arbitrary limits. It inherits all limits set by the underlying database implementation.
All file-based databases must provide a way of setting the file mode of a new created database, if that is possible at all. The file mode is commonly passed as the fourth argument to dba_open() or dba_popen().
You can access all entries of a database in a linear way by using the dba_firstkey() and dba_nextkey() functions. You may not change the database while traversing it.
Example 2. Traversing a database <?php # ...open database... $key = dba_firstkey($id); while($key != false) { if(...) { # remember the key to perform some action later $handle_later[] = $key; } $key = dba_nextkey($id); } for($i = 0; $i < count($handle_later); $i++) dba_delete($handle_later[$i], $id); ?> |
void dba_close
(int handle);dba_close() closes the established database and frees all resources specified by handle.
handle is a database handle returned by dba_open().
dba_close() does not return any value.
See also: dba_open() dba_popen()
string dba_delete
(string key, int handle);dba_delete() deletes the entry specified by key from the database specified with handle.
key is the key of the entry which is deleted.
handle is a database handle returned by dba_open().
dba_delete() returns true or false, if the entry is deleted or not deleted, respectively.
See also: dba_exists() dba_fetch() dba_insert() dba_replace()
bool dba_exists
(string key, int handle);dba_exists() checks whether the specified key exists in the database specified by handle.
key is the key the check is performed for.
handle is a database handle returned by dba_open().
dba_exists() returns true or false, if the key is found or not found, respectively.
See also: dba_fetch() dba_delete() dba_insert() dba_replace()
string dba_fetch
(string key, int handle);dba_fetch() fetches the data specified by key from the database specified with handle.
key is the key the data is specified by.
handle is a database handle returned by dba_open().
dba_fetch() returns the associated string or false, if the key/data pair is found or not found, respectively.
See also: dba_exists() dba_delete() dba_insert() dba_replace()
string dba_firstkey
(int handle);dba_firstkey() returns the first key of the database specified by handle and resets the internal key pointer. This permits a linear search through the whole database.
handle is a database handle returned by dba_open().
dba_firstkey() returns the key or false depending on whether it succeeds or fails, respectively.
See also: dba_nextkey()
bool dba_insert
(string key, string value, int handle);dba_insert() inserts the entry described with key and value into the database specified by handle. It fails, if an entry with the same key already exists.
key is the key of the entry to be inserted.
value is the value to be inserted.
handle is a database handle returned by dba_open().
dba_insert() returns true or false, depending on whether it succeeds of fails, respectively.
See also: dba_exists() dba_delete() dba_fetch() dba_replace()
string dba_nextkey
(int handle);dba_nextkey() returns the next key of the database specified by handle and increments the internal key pointer.
handle is a database handle returned by dba_open().
dba_nextkey() returns the key or false depending on whether it succeeds or fails, respectively.
See also: dba_firstkey()
int dba_popen
(string path, string mode, string handler, [...]);dba_popen() establishes a persistent database instance for path with mode using handler.
path is commonly a regular path in your filesystem.
mode is "r" for read access, "w" for read/write access to an already existing database, "c" for read/write access and database creation if it doesn't currently exist, and "n" for create, truncate and read/write access.
handler is the name of the handler which shall be used for accessing path. It is passed all optional parameters given to dba_popen() and can act on behalf of them.
dba_popen() returns a positive handler id or false, in the case the open is successful or fails, respectively.
See also: dba_open() dba_close()
int dba_open
(string path, string mode, string handler, [...]);dba_open() establishes a database instance for path with mode using handler.
path is commonly a regular path in your filesystem.
mode is "r" for read access, "w" for read/write access to an already existing database, "c" for read/write access and database creation if it doesn't currently exist, and "n" for create, truncate and read/write access.
handler is the name of the handler which shall be used for accessing path. It is passed all optional parameters given to dba_open() and can act on behalf of them.
dba_open() returns a positive handler id or false, in the case the open is successful or fails, respectively.
See also: dba_popen() dba_close()
bool dba_optimize
(int handle);dba_optimize() optimizes the underlying database specified by handle.
handle is a database handle returned by dba_open().
dba_optimize() returns true or false, if the optimization succeeds or fails, respectively.
See also: dba_sync()
bool dba_replace
(string key, string value, int handle);dba_replace() replaces or inserts the entry described with key and value into the database specified by handle.
key is the key of the entry to be inserted.
value is the value to be inserted.
handle is a database handle returned by dba_open().
dba_replace() returns true or false, depending on whether it succeeds of fails, respectively.
See also: dba_exists() dba_delete() dba_fetch() dba_insert()
bool dba_sync
(int handle);dba_sync() synchronizes the database specified by handle. This will probably trigger a physical write to disk, if supported.
handle is a database handle returned by dba_open().
dba_sync() returns true or false, if the synchronization succeeds or fails, respectively.
See also: dba_optimize()
These functions allow you to access records stored in dBase-format (dbf) databases.
There is no support for indexes or memo fields. There is no support for locking, too. Two concurrent webserver processes modifying the same dBase file will very likely ruin your database.
Unlike SQL databases, dBase "databases" cannot change the database definition afterwards. Once the file is created, the database definition is fixed. There are no indexes that speed searching or otherwise organize your data. dBase files are simple sequential files of fixed length records. Records are appended to the end of the file and delete records are kept until you call dbase_pack()().
We recommend that you do not use dBase files as your production database. Choose any real SQL server instead; MySQL or Postgres are common choices with PHP. dBase support is here to allow you to import and export data to and from your web database, since the file format is commonly understood with Windows spreadsheets and organizers. Import and export of data is about all that dBase support is good for.
int dbase_create
(string filename, array fields);The fields parameter is an array of arrays, each array describing the format of one field in the database. Each field consists of a name, a character indicating the field type, a length, and a precision.
The types of fields available are:
Boolean. These do not have a length or precision.
Memo. (Note that these aren't supported by PHP.) These do not have a length or precision.
Date (stored as YYYYMMDD). These do not have a length or precision.
Number. These have both a length and a precision (the number of digits after the decimal point).
String.
If the database is successfully created, a dbase_identifier is returned, otherwise false is returned.
Example 1. Creating a dBase database file // "database" name $dbname = "/tmp/test.dbf"; // database "definition" $def = array( array("date", "D"), array("name", "C", 50), array("age", "N", 3, 0), array("email", "C", 128), array("ismember", "L") ); // creation if (!dbase_create($dbname, $def)) print "<strong>Error!</strong>"; |
int dbase_open
(string filename, int flags);The flags correspond to those for the open() system call. (Typically 0 means read-only, 1 means write-only, and 2 means read and write.)
Returns a dbase_identifier for the opened database, or false if the database couldn't be opened.
bool dbase_close
(int dbase_identifier);Closes the database associated with dbase_identifier.
bool dbase_pack
(int dbase_identifier);Packs the specified database (permanently deleting all records marked for deletion using dbase_delete_record().
bool dbase_add_record
(int dbase_identifier, array record);Adds the data in the record to the database. If the number of items in the supplied record isn't equal to the number of fields in the database, the operation will fail and false will be returned.
bool dbase_replace_record
(int dbase_identifier, array record, int dbase_record_number);Replaces the data associated with the record record_number with the data in the record in the database. If the number of items in the supplied record is not equal to the number of fields in the database, the operation will fail and false will be returned.
dbase_record_number is an integer which spans from 1 to the number of records in the database (as returned by dbase_numrecords()).
bool dbase_delete_record
(int dbase_identifier, int record);Marks record to be deleted from the database. To actually remove the record from the database, you must also call dbase_pack().
array dbase_get_record
(int dbase_identifier, int record);Returns the data from record in an array. The array is indexed starting at 0, and includes an associative member named 'deleted' which is set to 1 if the record has been marked for deletion (see dbase_delete_record().
Each field is converted to the appropriate PHP type. (Dates are left as strings.)
array dbase_get_record_with_names
(int dbase_identifier, int record);Returns the data from record in an associative array. The array also includes an associative member named 'deleted' which is set to 1 if the record has been marked for deletion (see dbase_delete_record().
Each field is converted to the appropriate PHP type. (Dates are left as strings.)
int dbase_numfields
(int dbase_identifier);Returns the number of fields (columns) in the specified database. Field numbers are between 0 and dbase_numfields($db)-1, while record numbers are between 1 and dbase_numrecords($db).
Example 1. Using dbase_numfields() $rec = dbase_get_record($db, $recno); $nf = dbase_numfields($db); for ($i=0; $i < $nf; $i++) { print $rec[$i]."<br>\n"; } |
These functions allow you to store records stored in a dbm-style database. This type of database (supported by the Berkeley db, gdbm, and some system libraries, as well as a built-in flatfile library) stores key/value pairs (as opposed to the full-blown records supported by relational databases).
Example 1. dbm example $dbm = dbmopen("lastseen", "w"); if (dbmexists($dbm, $userid)) { $last_seen = dbmfetch($dbm, $userid); } else { dbminsert($dbm, $userid, time()); } do_stuff(); dbmreplace($dbm, $userid, time()); dbmclose($dbm); |
int dbmopen
(string filename, string flags);The first argument is the full-path filename of the dbm file to be opened and the second is the file open mode which is one of "r", "n", "c" or "w" for read-only, new (implies read-write, and most likely will truncate an already-existing database of the same name), create (implies read-write, and will not truncate an already-existing database of the same name) and read-write respectively.
Returns an identifer to be passed to the other dbm functions on success, or false on failure.
If ndbm support is used, ndbm will actually create filename.dir and filename.pag files. gdbm only uses one file, as does the internal flat-file support, and Berkeley db creates a filename.db file. Note that PHP does its own file locking in addition to any file locking that may be done by the dbm library itself. PHP does not delete the .lck files it creates. It uses these files simply as fixed inodes on which to do the file locking. For more information on dbm files, see your Unix man pages, or obtain GNU's gdbm from ftp://prep.ai.mit.edu/pub/gnu.
bool dbmexists
(int dbm_identifier, string key);Returns true if there is a value associated with the key.
int dbminsert
(int dbm_identifier, string key, string value);Adds the value to the database with the specified key.
Returns -1 if the database was opened read-only, 0 if the insert was successful, and 1 if the specified key already exists. (To replace the value, use dbmreplace().)
bool dbmreplace
(int dbm_identifier, string key, string value);Replaces the value for the specified key in the database.
This will also add the key to the database if it didn't already exist.
bool dbmdelete
(int dbm_identifier, string key);Deletes the value for key in the database.
Returns false if the key didn't exist in the database.
string dbmfirstkey
(int dbm_identifier);Returns the first key in the database. Note that no particular order is guaranteed since the database may be built using a hash-table, which doesn't guarantee any ordering.
string dbmnextkey
(int dbm_identifier, string key);Returns the next key after key. By calling dbmfirstkey() followed by successive calls to dbmnextkey() it is possible to visit every key/value pair in the dbm database. For example:
Example 1. Visiting every key/value pair in a dbm database. $key = dbmfirstkey($dbm_id); while ($key) { echo "$key = " . dbmfetch($dbm_id, $key) . "\n"; $key = dbmnextkey($dbm_id, $key); } |
int chdir
(string directory);Changes PHP's current directory to directory. Returns FALSE if unable to change directory, TRUE otherwise.
new dir
(string directory);A pseudo-object oriented mechanism for reading a directory. The given directory is opened. Two properties are available once directory has been opened. The handle property can be used with other directory functions such as readdir(), rewinddir() and closedir(). The path property is set to path the directory that was opened. Three methods are available: read, rewind and close.
Example 1. Dir() Example $d = dir("/etc"); echo "Handle: ".$d->handle."<br>\n"; echo "Path: ".$d->path."<br>\n"; while($entry=$d->read()) { echo $entry."<br>\n"; } $d->close(); |
void closedir
(int dir_handle);Closes the directory stream indicated by dir_handle. The stream must have previously been opened by opendir().
int opendir
(string path);Returns a directory handle to be used in subsequent closedir(), readdir(), and rewinddir() calls.
string readdir
(int dir_handle);Returns the filename of the next file from the directory. The filenames are not returned in any particular order.
Example 1. List all files in the current directory <?php $handle=opendir('.'); echo "Directory handle: $handle\n"; echo "Files:\n"; while ($file = readdir($handle)) { echo "$file\n"; } closedir($handle); ?> |
int dl
(string library);Loads the PHP extension defined in library. See also the extension_dir configuration directive.
string escapeshellcmd
(string command);EscapeShellCmd() escapes any characters in a string that might be used to trick a shell command into executing arbitrary commands. This function should be used to make sure that any data coming from user input is escaped before this data is passed to the exec() or system() functions. A standard use would be:
system(EscapeShellCmd($cmd))
string exec
(string command, string [array], int [return_var]);exec() executes the given command, however it does not output anything. It simply returns the last line from the result of the command. If you need to execute a command and have all the data from the command passed directly back without any interference, use the PassThru() function.
If the array argument is present, then the specified array will be filled with every line of output from the command. Note that if the array already contains some elements, exec() will append to the end of the array. If you do not want the function to append elements, call unset() on the array before passing it to exec().
If the return_var argument is present along with the array argument, then the return status of the executed command will be written to this variable.
Note that if you are going to allow data coming from user input to be passed to this function, then you should be using EscapeShellCmd() to make sure that users cannot trick the system into executing arbitrary commands.
See also system(), PassThru(), popen() and EscapeShellCmd().
string system
(string command, int [return_var]);System() is just like the C version of the function in that it executes the given command and outputs the result. If a variable is provided as the second argument, then the return status code of the executed command will be written to this variable.
Note, that if you are going to allow data coming from user input to be passed to this function, then you should be using the EscapeShellCmd() function to make sure that users cannot trick the system into executing arbitrary commands.
The System() call also tries to automatically flush the web server's output buffer after each line of output if PHP is running as a server module.
If you need to execute a command and have all the data from the command passed directly back without any interference, use the PassThru() function. See also the exec() and popen() functions.
string passthru
(string command, int [return_var]);The passthru() function is similar to the Exec() function in that it executes a command. If the return_var argument is present, the return status of the Unix command will be placed here. This function should be used in place of Exec() or System() when the output from the Unix command is binary data which needs to be passed directly back to the browser. A common use for this is to execute something like the pbmplus utilities that can output an image stream directly. By setting the content-type to image/gif and then calling a pbmplus program to output a gif, you can create PHP scripts that output images directly.
See also exec() and fpassthru().
Forms Data Format (FDF) is a format for handling forms within PDF documents. You should read the documentation at http://partners.adobe.com/asn/developer/acrosdk/main.html for more information on what FDF is and how it is used in general.
Note: Currently Adobe only provides a libc5 compatible version for Linux. Tests with glibc2 resulted in a segmentation fault. If somebody is able to make it work, please comment on this page.
The general idea of FDF is similar to HTML forms. The diffence is basically the format how filled in data is transmitted to the server when the submit button is pressed (this is actually the Form Data Format) and the format of the form itself (which is the Portable Document Format, PDF). Processing the FDF data is one of the features provided by the fdf functions. But there is more. One may as well take an existing PDF form and populated the input fields with data without modifying the form itself. In such a case one would create a FDF document (fdf_create()) set the values of each input field (fdf_set_value()) and associate it with a PDF form (fdf_set_file()). Finally it has to be sent to the browser with MimeType application/vnd.fdf. The Acrobat reader plugin of your browser recognizes the MimeType, reads the associated PDF form and fills in the data from the FDF document.
The following examples shows just the evaluation of form data.
Example 1. Evaluating a FDF document <?php // Save the FDF data into a temp file $fdffp = fopen("test.fdf", "w"); fwrite($fdffp, $HTTP_FDF_DATA, strlen($HTTP_FDF_DATA)); fclose($fdffp); // Open temp file and evaluate data // The pdf form contained several input text fields with the names // volume, date, comment, publisher, preparer, and two checkboxes // show_publisher and show_preparer. $fdf = fdf_open("test.fdf"); $volume = fdf_get_value($fdf, "volume"); echo "The volume field has the value '<B>$volume</B>'<BR>"; $date = fdf_get_value($fdf, "date"); echo "The date field has the value '<B>$date</B>'<BR>"; $comment = fdf_get_value($fdf, "comment"); echo "The comment field has the value '<B>$comment</B>'<BR>"; if(fdf_get_value($fdf, "show_publisher") == "On") { $publisher = fdf_get_value($fdf, "publisher"); echo "The publisher field has the value '<B>$publisher</B>'<BR>"; } else echo "Publisher shall not be shown.<BR>"; if(fdf_get_value($fdf, "show_preparer") == "On") { $preparer = fdf_get_value($fdf, "preparer"); echo "The preparer field has the value '<B>$preparer</B>'<BR>"; } else echo "Preparer shall not be shown.<BR>"; fdf_close($fdf); ?> |
int fdf_open
(string filename);The fdf_open() function opens a file with form data. This file must contain the data as returned from a PDF form. Currently, the file has to be created 'manually' by using fopen() and writing the content of HTTP_FDF_DATA with fwrite() into it. A mechanism like for HTML form data where for each input field a variable is created does not exist.
Example 1. Accessing the form data <?php // Save the FDF data into a temp file $fdffp = fopen("test.fdf", "w"); fwrite($fdffp, $HTTP_FDF_DATA, strlen($HTTP_FDF_DATA)); fclose($fdffp); // Open temp file and evaluate data $fdf = fdf_open("test.fdf"); ... fdf_close($fdf); ?> |
See also fdf_close().
void fdf_close
(int fdf_document);The fdf_close() function closes the FDF document.
See also fdf_open().
int fdf_create
(void );The fdf_create() creates a new FDF document. This function is needed if one would like to populate input fields in a PDF document with data.
Example 1. Populating a PDF document <?php $outfdf = fdf_create(); fdf_set_value($outfdf, "volume", $volume, 0); fdf_set_file($outfdf, "http:/testfdf/resultlabel.pdf"); fdf_save($outfdf, "outtest.fdf"); fdf_close($outfdf); Header("Content-type: application/vnd.fdf"); $fp = fopen("outtest.fdf", "r"); fpassthru($fp); unlink("outtest.fdf"); ?> |
See also fdf_close(), fdf_save(), fdf_open().
int fdf_save
(string filename);The fdf_save() function saves a FDF document. The FDF Toolkit provides a way to output the document to stdout if the parameter filename is '.'. This does not work if PHP is used as an apache module. In such a case one will have to write to a file and use e.g. fpassthru(). to output it.
See also fdf_close() and example for fdf_create().
string fdf_get_value
(int fdf_document, string fieldname);The fdf_get_value() function returns the value of a field.
See also fdf_set_value().
void fdf_set_value
(int fdf_document, string fieldname, string value, int isName);The fdf_set_value() function sets the value of a field. The last parameter determines if the field value is to be converted to a PDF Name (isName = 1) or set to a PDF String (isName = 0).
See also fdf_get_value().
string fdf_next_field_name
(int fdf_document, string fieldname);The fdf_next_field_name() function returns the name of the field after the field in fieldname or the field name of the first field if the second paramter is NULL.
See also fdf_set_field(), fdf_get_field().
void fdf_set_ap
(int fdf_document, string field_name, int face, string filename, int page_number);The fdf_set_ap() function sets the appearance of a field (i.e. the value of the /AP key). The possible values of face are 1=FDFNormalAP, 2=FDFRolloverAP, 3=FDFDownAP.
void fdf_set_status
(int fdf_document, string status);The fdf_set_status() sets the value of the /STATUS key.
See also fdf_get_status().
string fdf_get_status
(int fdf_document);The fdf_get_status() returns the value of the /STATUS key.
See also fdf_set_status().
void fdf_set_file
(int fdf_document, string filename);The fdf_set_file() sets the value of the /F key. The /F key is just a reference to a PDF form which is to be populated with data. In a web environment it is a URL (e.g. http:/testfdf/resultlabel.pdf).
See also fdf_get_file() and example for fdf_create().
string fdf_get_file
(int fdf_document);The fdf_set_file() returns the value of the /F key.
See also fdf_set_file().
These functions allow read-only access to data stored in filePro databases.
filePro is a registered trademark of Fiserv, Inc. You can find more information about filePro at http://www.fileproplus.com/.
bool filepro
(string directory);This reads and verifies the map file, storing the field count and info.
No locking is done, so you should avoid modifying your filePro database while it may be opened in PHP.
string filepro_fieldname
(int field_number);Returns the name of the field corresponding to field_number.
string filepro_fieldtype
(int field_number);Returns the edit type of the field corresponding to field_number.
int filepro_fieldwidth
(int field_number);Returns the width of the field corresponding to field_number.
string filepro_retrieve
(int row_number, int field_number);Returns the data from the specified location in the database.
int filepro_fieldcount
(void);Returns the number of fields (columns) in the opened filePro database.
See also filepro().
int filepro_rowcount
(void);Returns the number of rows in the opened filePro database.
See also filepro().
string basename
(string path);Given a string containing a path to a file, this function will return the base name of the file.
On Windows, both slash (/) and backslash (\) are used as path separator character. In other environments, it is the forward slash (/).
Example 1. basename() example $path = "/home/httpd/html/index.php3"; $file = basename($path); // $file is set to "index.php3" |
See also: dirname()
int chgrp
(string filename, mixed group);Attempts to change the group of the file filename to group. Only the superuser may change the group of a file arbitrarily; other users may change the group of a file to any group of which that user is a member.
Returns true on success; otherwise returns false.
On Windows, does nothing and returns true.
int chmod
(string filename, int mode);Attempts to change the mode of the file specified by filename to that given in mode.
Note that mode is not automatically assumed to be an octal value. To ensure the expected operation, you need to prefix mode with a zero (0):
chmod( "/somedir/somefile", 755 ); // decimal; probably incorrect chmod( "/somedir/somefile", 0755 ); // octal; correct value of mode
Returns true on success and false otherwise.
int chown
(string filename, mixed user);Attempts to change the owner of the file filename to user user. Only the superuser may change the owner of a file.
Returns true on success; otherwise returns false.
Note: On Windows, does nothing and returns true.
See also chown() and chmod().
void clearstatcache
(void);Invoking the stat or lstat system call on most systems is quite expensive. Therefore, the result of the last call to any of the status functions (listed below) is stored for use on the next such call using the same filename. If you wish to force a new status check, for instance if the file is being checked many times and may change or disappear, use this function to clear the results of the last call from memory.
This value is only cached for the lifetime of a single request.
Affected functions include stat(), lstat(), file_exists(), is_writeable(), is_readable(), is_executable(), is_file(), is_dir(), is_link(), filectime(), fileatime(), filemtime(), fileinode(), filegroup(), fileowner(), filesize(), filetype(), and fileperms().
int copy
(string source, string dest);Makes a copy of a file. Returns true if the copy succeeded, false otherwise.
Example 1. copy() example if (!copy($file, $file.'.bak')) { print("failed to copy $file...<br>\n"); } |
See also: rename()
void delete
(string file);This is a dummy manual entry to satisfy those people who are looking for unlink() or unset() in the wrong place.
See also: unlink() to delete files, unset() to delete variables.
string dirname
(string path);Given a string containing a path to a file, this function will return the name of the directory.
On Windows, both slash (/) and backslash (\) are used as path separator character. In other environments, it is the forward slash (/).
Example 1. dirname() example $path = "/etc/passwd"; $file = dirname($path); // $file is set to "/etc" |
See also: basename()
float diskfreespace
(string directory);Given a string containing a directory, this function will return the number of bytes available on the corresponding disk.
Example 1. diskfreespace() example $df = diskfreespace("/"); // $df contains the number of bytes available on "/" |
int fclose
(int fp);The file pointed to by fp is closed.
Returns true on success and false on failure.
The file pointer must be valid, and must point to a file successfully opened by fopen() or fsockopen().
int feof
(int fp);Returns true if the file pointer is at EOF or an error occurs; otherwise returns false.
The file pointer must be valid, and must point to a file successfully opened by fopen(), popen(), or fsockopen().
string fgetc
(int fp);Returns a string containing a single character read from the file pointed to by fp. Returns FALSE on EOF (as does feof()).
The file pointer must be valid, and must point to a file successfully opened by fopen(), popen(), or fsockopen().
See also fread(), fopen(), popen(), fsockopen(), and fgets().
array fgetcsv
(int fp, int length, string [delimiter]);Similar to fgets() except that fgetcsv() parses the line it reads for fields in CSV format and returns an array containing the fields read. The field delimiter is a comma, unless you specifiy another delimiter with the optional third parameter.
fp must be a valid file pointer to a file successfully opened by fopen(), popen(), or fsockopen()
length must be greater than the longest line to be found in the CSV file (allowing for trailing line-end characters).
fgetcsv() returns false on error, including end of file.
NB A blank line in a CSV file will be returned as an array comprising just one single null field, and will not be treated as an error.
Example 1. fgetcsv() example - Read and print entire contents of a CSV file $row=1; $fp = fopen("test.csv","r"); while ($data = fgetcsv($fp,1000, ",")) { $num = count($data); print "<p> $num fields in line $row: <br>"; $row++; for ( $c=0; $c<$num; $c++ ) print $data[$c] . "<br>"; } fclose($fp); |
string fgets
(int fp, int length);Returns a string of up to length - 1 bytes read from the file pointed to by fp. Reading ends when length - 1 bytes have been read, on a newline (which is included in the return value), or on EOF (whichever comes first).
If an error occurs, returns false.
Common Pitfalls:
People used to the 'C' semantics of fgets should note the difference in how EOF is returned.
The file pointer must be valid, and must point to a file successfully opened by fopen(), popen(), or fsockopen().
A simple example follows:
Example 1. Reading a file line by line $fd = fopen("/tmp/inputfile.txt", "r"); while ($buffer = fgets($fd, 4096)) { echo $buffer; } fclose($fd); |
See also fread(), fopen(), popen(), fgetc(), and fsockopen().
string fgetss
(int fp, int length);Identical to fgets(), except that fgetss attempts to strip any HTML and PHP tags from the text it reads.
See also fgets(), fopen(), fsockopen(), popen(), and strip_tags().
array file
(string filename);Identical to readfile(), except that file() returns the file in an array. Each element of the array corresponds to a line in the file, with the newline still attached.
See also readfile(), fopen(), and popen().
int file_exists
(string filename);Returns true if the file specified by filename exists; false otherwise.
The results of this function are cached. See clearstatcache() for more details.
int fileatime
(string filename);Returns the time the file was last accessed, or false in case of an error.
The results of this function are cached. See clearstatcache() for more details.
int filectime
(string filename);Returns the time the file was last changed, or false in case of an error.
The results of this function are cached. See clearstatcache() for more details.
int filegroup
(string filename);Returns the group ID of the owner of the file, or false in case of an error.
The results of this function are cached. See clearstatcache() for more details.
int fileinode
(string filename);Returns the inode number of the file, or false in case of an error.
The results of this function are cached. See clearstatcache() for more details.
int filemtime
(string filename);Returns the time the file was last modified, or false in case of an error.
The results of this function are cached. See clearstatcache() for more details.
int fileowner
(string filename);Returns the user ID of the owner of the file, or false in case of an
The results of this function are cached. See clearstatcache() for more details. error.
int fileperms
(string filename);Returns the permissions on the file, or false in case of an error.
The results of this function are cached. See clearstatcache() for more details.
int filesize
(string filename);Returns the size of the file, or false in case of an error.
The results of this function are cached. See clearstatcache() for more details.
string filetype
(string filename);Returns the type of the file. Possible values are fifo, char, dir, block, link, file, and unknown.
Returns false if an error occurs.
The results of this function are cached. See clearstatcache() for more details.
bool flock
(int fp, int operation);PHP supports a portable way of locking complete files in an advisory way (which means all accessing programs have to use the same way of locking or it will not work).
flock() operates on fp which must be an open file pointer. operation is one of the following values:
To acquire a shared lock (reader), set operation to 1.
To acquire an exclusive lock (writer), set operation to 2.
To release a lock (shared or exclusive), set operation to 3.
If you don't want flock() to block while locking, add 4 to operation.
flock() allows you to perform a simple reader/writer model which can be used on virtually every platform (including most Unices and even Windows).
flock() returns true on success and false on error (e.g. when a lock could not be acquired).
int fopen
(string filename, string mode);If filename begins with "http://" (not case sensitive), an HTTP 1.0 connection is opened to the specified server and a file pointer is returned to the beginning of the text of the response.
Does not handle HTTP redirects, so you must include trailing slashes on directories.
If filename begins with "ftp://" (not case sensitive), an ftp connection to the specified server is opened and a pointer to the requested file is returned. If the server does not support passive mode ftp, this will fail. You can open files for either reading and writing via ftp (but not both simultaneously).
If filename begins with anything else, the file will be opened from the filesystem, and a file pointer to the file opened is returned.
If the open fails, the function returns false.
mode may be any of the following:
'r' - Open for reading only; place the file pointer at the beginning of the file.
'r+' - Open for reading and writing; place the file pointer at the beginning of the file.
'w' - Open for writing only; place the file pointer at the beginning of the file and truncate the file to zero length. If the file does not exist, attempt to create it.
'w+' - Open for reading and writing; place the file pointer at the beginning of the file and truncate the file to zero length. If the file does not exist, attempt to create it.
'a' - Open for writing only; place the file pointer at the end of the file. If the file does not exist, attempt to create it.
'a+' - Open for reading and writing; place the file pointer at the end of the file. If the file does not exist, attempt to create it.
Example 1. fopen() example $fp = fopen("/home/rasmus/file.txt", "r"); $fp = fopen("http://www.php.net/", "r"); $fp = fopen("ftp://user:password@example.com/", "w"); |
If you are experiencing problems with reading and writing to files and you're using the server module version of PHP, remember to make sure that the files and directories you're using are accessible to the server process.
On the Windows platform, be careful to escape any backslashes used in the path to the file, or use forward slashes.
$fp = fopen("c:\\data\\info.txt", "r");
See also fclose(), fsockopen(), and popen().
int fpassthru
(int fp);Reads to EOF on the given file pointer and writes the results to standard output.
If an error occurs, fpassthru() returns false.
The file pointer must be valid, and must point to a file successfully opened by fopen(), popen(), or fsockopen(). The file is closed when fpassthru() is done reading it (leaving fp useless).
If you just want to dump the contents of a file to stdout you may want to use the readfile(), which saves you the fopen() call.
See also readfile(), fopen(), popen(), and fsockopen()
int fputs
(int fp, string str, int [length]);fputs() is an alias to fwrite(), and is identical in every way. Note that the length parameter is optional and if not specified the entire string will be written.
string fread
(int fp, int length);fread() reads up to length bytes from the file pointer referenced by fp. Reading stops when length bytes have been read or EOF is reached, whichever comes first.
// get contents of a file into a string $filename = "/usr/local/something.txt"; $fd = fopen( $filename, "r" ); $contents = fread( $fd, filesize( $filename ) ); fclose( $fd );
See also fwrite(), fopen(), fsockopen(), popen(), fgets(), fgetss(), file(), and fpassthru().
int fseek
(int fp, int offset);Sets the file position indicator for the file referenced by fp to offset bytes into the file stream. Equivalent to calling (in C) fseek( fp, offset, SEEK_SET ).
Upon success, returns 0; otherwise, returns -1. Note that seeking past EOF is not considered an error.
May not be used on file pointers returned by fopen() if they use the "http://" or "ftp://" formats.
int ftell
(int fp);Returns the position of the file pointer referenced by fp; i.e., its offset into the file stream.
If an error occurs, returns false.
The file pointer must be valid, and must point to a file successfully opened by fopen() or popen().
int fwrite
(int fp, string string, int [length]);fwrite() writes the contents of string to the file stream pointed to by fp. If the length argument is given, writing will stop after length bytes have been written or the end of string is reached, whichever comes first.
Note that if the length argument is given, then the magic_quotes_runtime configuration option will be ignored and no slashes will be stripped from string.
See also fread(), fopen(), fsockopen(), popen(), and fputs().
int fwrite
(int fp, int buffer);set_file_buffer() sets the buffering for write operations on the given filepointer fp to buffer bytes. If buffer is 0 then write operations are unbuffered.
The function returns 0 on success, or EOF if the request cannot be honored.
Note that the default for any fopen with calling set_file_buffer is 8K.
See also fopen().
bool is_dir
(string filename);Returns true if the filename exists and is a directory.
The results of this function are cached. See clearstatcache() for more details.
bool is_executable
(string filename);Returns true if the filename exists and is executable.
The results of this function are cached. See clearstatcache() for more details.
bool is_file
(string filename);Returns true if the filename exists and is a regular file.
The results of this function are cached. See clearstatcache() for more details.
bool is_link
(string filename);Returns true if the filename exists and is a symbolic link.
The results of this function are cached. See clearstatcache() for more details.
bool is_readable
(string filename);Returns true if the filename exists and is readable.
Keep in mind that PHP may be accessing the file as the user id that the web server runs as (often 'nobody'). Safe mode limitations are not taken into account.
The results of this function are cached. See clearstatcache() for more details.
See also is_writeable().
bool is_writeable
(string filename);Returns true if the filename exists and is writeable. The filename argument may be a directory name allowing you to check if a directory is writeable.
Keep in mind that PHP may be accessing the file as the user id that the web server runs as (often 'nobody'). Safe mode limitations are not taken into account.
The results of this function are cached. See clearstatcache() for more details.
See also is_readable().
int link
(string target, string link);Link() creates a hard link.
See also the symlink() to create soft links, and readlink() along with linkinfo().
int linkinfo
(string path);Linkinfo() returns the st_dev field of the UNIX C stat structure returned by the lstat system call. This function is used to verify if a link (pointed to by path) really exists (using the same method as the S_ISLNK macro defined in stat.h). Returns 0 or FALSE in case of error.
See also symlink(), link(), and readlink().
int mkdir
(string pathname, int mode);Attempts to create the directory specified by pathname.
Note that you probably want to specify the mode as an octal number, which means it should have a leading zero.
mkdir("/path/to/my/dir", 0700);
Returns true on success and false on failure.
See also rmdir().
int pclose
(int fp);Closes a file pointer to a pipe opened by popen().
The file pointer must be valid, and must have been returned by a successful call to popen().
Returns the termination status of the process that was run.
See also popen().
int popen
(string command, string mode);Opens a pipe to a process executed by forking the command given by command.
Returns a file pointer identical to that returned by fopen(), except that it is unidirectional (may only be used for reading or writing) and must be closed with pclose(). This pointer may be used with fgets(), fgetss(), and fputs().
If an error occurs, returns false.
$fp = popen( "/bin/ls", "r" );
See also pclose().
int readfile
(string filename);Reads a file and writes it to standard output.
Returns the number of bytes read from the file. If an error occurs, false is returned and unless the function was called as @readfile, an error message is printed.
If filename begins with "http://" (not case sensitive), an HTTP 1.0 connection is opened to the specified server and the text of the response is written to standard output.
Does not handle HTTP redirects, so you must include trailing slashes on directories.
If filename begins with "ftp://" (not case sensitive), an ftp connection to the specified server is opened and the requested file is written to standard output. If the server does not support passive mode ftp, this will fail.
If filename begins with neither of these strings, the file will be opened from the filesystem and its contents written to standard output.
See also fpassthru(), file(), fopen(), include(), require(), and virtual().
string readlink
(string path);Readlink() does the same as the readlink C function and returns the contents of the symbolic link path or 0 in case of error.
See also symlink(), readlink() and linkinfo().
int rename
(string oldname, string newname);Attempts to rename oldname to newname.
Returns true on success and false on failure.
int rewind
(int fp);Sets the file position indicator for fp to the beginning of the file stream.
If an error occurs, returns 0.
The file pointer must be valid, and must point to a file successfully opened by fopen().
int rmdir
(string dirname);Attempts to remove the directory named by pathname. The directory must be empty, and the relevant permissions must permit this.
If an error occurs, returns 0.
See also mkdir().
array stat
(string filename);Gathers the statistics of the file named by filename.
Returns an array with the statistics of the file with the following elements:
device
inode
inode protection mode
number of links
user id of owner
group id owner
device type if inode device *
size in bytes
time of last access
time of last modification
time of last change
blocksize for filesystem I/O *
number of blocks allocated
The results of this function are cached. See clearstatcache() for more details.
array lstat
(string filename);Gathers the statistics of the file or symbolic link named by filename. This function is identical to the stat() function except that if the filename parameter is a symbolic link, the status of the symbolic link is returned, not the status of the file pointed to by the symbolic link.
Returns an array with the statistics of the file with the following elements:
device
inode
number of links
user id of owner
group id owner
device type if inode device *
size in bytes
time of last access
time of last modification
time of last change
blocksize for filesystem I/O *
number of blocks allocated
The results of this function are cached. See clearstatcache() for more details.
int symlink
(string target, string link);symlink() creates a symbolic link from the existing target with the specified name link.
See also link() to create hard links, and readlink() along with linkinfo().
string tempnam
(string dir, string prefix);Creates a unique temporary filename in the specified directory. If the directory does not exist, tempnam() may generate a filename in the system's temporary directory.
The behaviour of the tempnam() function is system dependent. On Windows the TMP environment variable will override the dir parameter, on Linux the TMPDIR environment variable has precedence, while SVR4 will always use your dir parameter if the directory it points to exists. Consult your system documentation on the tempnam(3) function if in doubt.
Returns the new temporary filename, or the null string on failure.
Example 1. tempnam() example $tmpfname = tempnam( "/tmp", "FOO" ); |
int touch
(string filename, int time);Attempts to set the modification time of the file named by filename to the value given by time. If the option time is not given, uses the present time.
If the file does not exist, it is created.
Returns true on success and false otherwise.
int umask
(int mask);Umask() sets PHP's umask to mask & 0777 and returns the old umask. When PHP is being used as a server module, the umask is restored when each request is finished.
Umask() without arguments simply returns the current umask.
int unlink
(string filename);Deletes filename. Similar to the Unix C unlink() function.
Returns 0 or FALSE on an error.
See also rmdir() for removing directories.
int header
(string string);The Header() function is used at the top of an HTML file to send raw HTTP header strings. See the HTTP 1.1 Specification for more information on raw http headers. Note: Remember that the Header() function must be called before any actual output is sent either by normal HTML tags or from PHP. It is a very common error to read code with include() or with auto_prepend and have spaces or empty lines in this code that force output before header() is called.
header("Location: http://www.php.net"); /* Redirect browser to PHP web site */ exit; /* Make sure that code below does not get executed when we redirect. */
PHP scripts often generate dynamic HTML that must not be cached by the client browser or any proxy caches between the server and the client browser. Many proxies and clients can be forced to disable caching with
header("Expires: Mon, 26 Jul 1997 05:00:00 GMT"); // Date in the past header("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT"); // always modified header("Cache-Control: no-cache, must-revalidate"); // HTTP/1.1 header("Pragma: no-cache"); // HTTP/1.0
int setcookie
(string name, string value, int expire, string path, string domain, int secure);setcookie() defines a cookie to be sent along with the rest of the header information. Cookies must be sent before any other headers are sent (this is a restriction of cookies, not PHP). This requires you to place calls to this function before any <html> or <head> tags.
All the arguments except the name argument are optional. If only the name argument is present, the cookie by that name will be deleted from the remote client. You may also replace any argument with an empty string ("") in order to skip that argument. The expire and secure arguments are integers and cannot be skipped with an empty string. Use a zero (0) instead. The expire argument is a regular Unix time integer as returned by the time() or mktime() functions. The secure indicates that the cookie should only be transmitted over a secure HTTPS connection.
Common Pitfalls:
Cookies will not become visible until the next loading of a page that the cookie should be visable for.
Multiple calls to setcookie() in the same script will be performed in the reverse order. If you are trying to delete one cookie before inserting another you should put the insert before the delete.
Some examples follow:
Example 1. setcookie() examples setcookie("TestCookie","Test Value"); setcookie("TestCookie",$value,time()+3600); /* expire in 1 hour */ setcookie("TestCookie",$value,time()+3600,"/~rasmus/",".utoronto.ca",1); |
Note that the value portion of the cookie will automatically be urlencoded when you send the cookie, and when it is received, it is automatically decoded and assigned to a variable by the same name as the cookie name. To see the contents of our test cookie in a script, simply use one of the following examples:
echo $TestCookie; echo $HTTP_COOKIE_VARS["TestCookie"];
For more information on cookies, see Netscape's cookie specification at http://www.netscape.com/newsref/std/cookie_spec.html.
Microsoft Internet Explorer 4 with Service Pack 1 applied does not correctly deal with cookies that have their path parameter set.
Netscape Communicator 4.05 and Microsoft Internet Explorer 3.x appear to handle cookies incorrectly when the path and time are not set.
Hyperwave has been developed at IICM in Graz. It started with the name Hyper-G and changed to Hyperwave when it was commercialised (If I remember properly it was in 1996).
Hyperwave is not free software. The current version, 4.1, is available at www.hyperwave.com. A time limited version can be ordered for free (30 days).
Hyperwave is an information system similar to a database (HIS, Hyperwave Information Server). Its focus is the storage and management of documents. A document can be any possible piece of data that may as well be stored in file. Each document is accompanied by its object record. The object record contains meta data for the document. The meta data is a list of attributes which can be extended by the user. Certain attributes are always set by the Hyperwave server, other may be modified by the user. An attribute is a name/value pair of the form name=value. The complete object record contains as many of those pairs as the user likes. The name of an attribute does not have to be unique, e.g. a title may appear several times within an object record. This makes sense if you want to specify a title in several languages. In such a case there is a convention, that each title value is preceded by the two letter language abbreviation followed by a colon, e.g. 'en:Title in English' or 'ge:Titel in deutsch'. Other attributes like a description or keywords are potential candidates. You may also replace the language abbreviation by any other string as long as it separated by colon from the rest of the attribute value.
Each object record has native a string representation with each name/value pair separated by a newline. The Hyperwave extension also knows a second representation which is an associated array with the attribute name being the key. Multilingual attribute values itself form another associated array with the key being the language abbreviation. Actually any multiple attribute forms an associated array with the string left to the colon in the attribute value being the key. (This is not fully implemented. Only the attributes Title, Description and Keyword are treated properly yet.)
Besides the documents, all hyper links contained in a document are stored as object records as well. Hyper links which are in a document will be removed from it and stored as individual objects, when the document is inserted into the database. The object record of the link contains information about where it starts and where it ends. In order to gain the original document you will have to retrieve the plain document without the links and the list of links and reinsert them (The functions hw_pipedocument() and hw_gettext() do this for you. The advantage of separating links from the document is obvious. Once a document to which a link is pointing to changes its name, the link can easily be modified accordingly. The document containing the link is not affected at all. You may even add a link to a document without modifying the document itself.
Saying that hw_pipedocument() and hw_gettext() do the link insertion automatically is not as simple as it sounds. Inserting links implies a certain hierarchy of the documents. On a web server this is given by the file system, but Hyperwave has its own hierarchy and names do not reflect the position of an object in that hierarchy. Therefore creation of links first of all requires a mapping from the Hyperwave hierarchy and namespace into a web hierarchy respective web namespace. The fundamental difference between Hyperwave and the web is the clear distinction between names and hierarchy in Hyperwave. The name does not contain any information about the objects position in the hierarchy. In the web the name also contains the information on where the object is located in the hierarchy. This leads to two possibles ways of mapping. Either the Hyperwave hierarchy and name of the Hyperwave object is reflected in the URL or the name only. To make things simple the second approach is used. Hyperwave object with name 'my_object' is mapped to 'http://host/my_object' disregarding where it resides in the Hyperwave hierarchy. An object with name 'parent/my_object' could be the child of 'my_object' in the Hyperwave hierarchy, though in a web namespace it appears to be just the opposite and the user might get confused. This can only be prevented by selecting reasonable object names.
Having made this decision a second problem arises. How do you involve PHP? The URL http://host/my_object will not call any PHP script unless you tell your web server to rewrite it to e.g. 'http://host/php3_script/my_object' and the script 'php3_script' evaluates the $PATH_INFO variable and retrieves the object with name 'my_object' from the Hyperwave server. Their is just one little drawback which can be fixed easily. Rewriting any URL would not allow any access to other document on the web server. A PHP script for searching in the Hyperwave server would be impossible. Therefore you will need at least a second rewriting rule to exclude certain URLS like all e.g. starting with http://host/Hyperwave. This is basically sharing of a namespace by the web and Hyperwave server.
Based on the above mechanism links are insert into documents.
It gets more complicated if PHP is not run as a server module or CGI script but as a standalone application e.g. to dump the content of the Hyperwave server on a CD-ROM. In such a case it makes sense to retain the Hyperwave hierarchy and map in onto the file system. This conflicts with the object names if they reflect its own hierarchy (e.g. by choosing names including '/'). Therefore '/' has to be replaced by another character, e.g. '_'. to be continued.
The network protocol to communicate with the Hyperwave server is called HG-CSP (Hyper-G Client/Server Protocol). It is based on messages to initiate certain actions, e.g. get object record. In early versions of the Hyperwave Server two native clients (Harmony, Amadeus) were provided for communication with the server. Those two disappeared when Hyperwave was commercialised. As a replacement a so called wavemaster was provided. The wavemaster is like a protocol converter from HTTP to HG-CSP. The idea is to do all the administration of the database and visualisation of documents by a web interface. The wavemaster implements a set of placeholders for certain actions to customise the interface. This set of placeholders is called the PLACE Language. PLACE lacks a lot of features of a real programming language and any extension to it only enlarges the list of placeholders. This has led to the use of JavaScript which IMO does not make life easier.
Adding Hyperwave support to PHP should fill in the gap of a missing programming language for interface customisation. It implements all the messages as defined by the HG-CSP but also provides more powerful commands to e.g. retrieve complete documents.
Hyperwave has its own terminology to name certain pieces of information. This has widely been taken over and extended. Almost all functions operate on one of the following data types.
object ID: An unique integer value for each object in the Hyperwave server. It is also one of the attributes of the object record (ObjectID). Object ids are often used as an input parameter to specify an object.
object record: A string with attribute-value pairs of the form attribute=value. The pairs are separated by a carriage return from each other. An object record can easily be converted into an object array with hw_object2array(). Several functions return object records. The names of those functions end with obj.
object array: An associated array with all attributes of an object. The key is the attribute name. If an attribute occurs more than once in an object record it will result in another indexed or associated array. Attributes which are language depended (like the title, keyword, description) will form an associated array with the key set to the language abbreviation. All other multiple attributes will form an indexed array. PHP functions never return object arrays.
hw_document: This is a complete new data type which holds the actual document, e.g. HTML, PDF etc. It is somewhat optimised for HTML documents but may be used for any format.
Several functions which return an array of object records do also return an associated array with statistical information about them. The array is the last element of the object record array. The statistical array contains the following entries:
Number of object records with attribute PresentationHints set to Hidden.
Number of object records with attribute PresentationHints set to CollectionHead.
Number of object records with attribute PresentationHints set to FullCollectionHead.
Index in array of object records with attribute PresentationHints set to CollectionHead.
Index in array of object records with attribute PresentationHints set to FullCollectionHead.
Total: Number of object records.
The Hyperwave extension is best used when PHP is compiled as an Apache module. In such a case the underlying Hyperwave server can be hidden from users almost completely if Apache uses its rewriting engine. The following instructions will explain this.
Since PHP with Hyperwave support built into Apache is intended to replace the native Hyperwave solution based on Wavemaster I will assume that the Apache server will only serve as a Hyperwave web interface. This is not necessary but it simplifies the configuration. The concept is quite simple. First of all you need a PHP script which evaluates the PATH_INFO variable and treats its value as the name of a Hyperwave object. Let's call this script 'Hyperwave'. The URL http://your.hostname/Hyperwave/name_of_object would than return the Hyperwave object with the name 'name_of_object'. Depending on the type of the object the script has to react accordingly. If it is a collection, it will probably return a list of children. If it is a document it will return the mime type and the content. A slight improvement can be achieved if the Apache rewriting engine is used. From the users point of view it would be more straight forward if the URL http://your.hostname/name_of_object would return the object. The rewriting rule is quite easy:
RewriteRule ^/(.*) /usr/local/apache/htdocs/HyperWave/$1 [L]
RewriteRule ^/hw/(.*) /usr/local/apache/htdocs/hw/$1 [L]
RewriteEngine on
to return the object itself
to allow searching
to identify yourself
to set your profile
one for each additional function like to show the object attributes, to show information about users, to show the status of the server, etc.
There are still some things todo:
The hw_InsertDocument has to be split into hw_InsertObject() and hw_PutDocument().
The names of several functions are not fixed, yet.
Most functions require the current connection as its first parameter. This leads to a lot of typing, which is quite often not necessary if there is just one open connection. A default connection will improve this.
array hw_children
(int connection, int objectID);Returns an array of object ids. Each id belongs to a child of the collection with ID objectID. The array contains all children both documents and collections.
array hw_childrenobj
(int connection, int objectID);Returns an array of object records. Each object record belongs to a child of the collection with ID objectID. The array contains all children both documents and collections.
int hw_close
(int connection);Returns false if connection is not a valid connection index, otherwise true. Closes down the connection to a Hyperwave server with the given connection index.
int hw_connect
(string host, int port, string username, string password);Opens a connection to a Hyperwave server and returns a connection index on success, or false if the connection could not be made. Each of the arguments should be a quoted string, except for the port number. The username and password arguments are optional and can be left out. In such a case no identification with the server will be done. It is similar to identify as user anonymous. This function returns a connection index that is needed by other Hyperwave functions. You can have multiple connections open at once. Keep in mind, that the password is not encrypted.
See also hw_pConnect().
int hw_cp
(int connection, array object_id_array, int destination id);Copies the objects with object ids as specified in the second parameter to the collection with the id destination id.
The value return is the number of copied objects.
See also hw_mv().
int hw_deleteobject
(int connection, int object_to_delete);Deletes the object with the given object id in the second parameter. It will delete all instances of the object.
Returns TRUE if no error occurs otherwise FALSE.
See also hw_mv().
int hw_docbyanchor
(int connection, int anchorID);Returns an th object id of the document to which anchorID belongs.
string hw_docbyanchorobj
(int connection, int anchorID);Returns an th object record of the document to which anchorID belongs.
string hw_documentattributes
(int hw_document);Returns the object record of the document.
See also hw_DocumentBodyTag(), hw_DocumentSize().
string hw_documentbodytag
(int hw_document);Returns the BODY tag of the document. If the document is an HTML document the BODY tag should be printed before the document.
See also hw_DocumentAttributes(), hw_DocumentSize().
string hw_documentcontent
(int hw_document);Returns the content of the document. If the document is an HTML document the content is everything after the BODY tag. Information from the HEAD and BODY tag is in the stored in the object record.
See also hw_DocumentAttributes(), hw_DocumentSize(), hw_DocumentSetContent().
string hw_documentsetcontent
(int hw_document, string content);Sets or replaces the content of the document. If the document is an HTML document the content is everything after the BODY tag. Information from the HEAD and BODY tag is in the stored in the object record. If you provide this information in the content of the document too, the Hyperwave server will change the object record accordingly when the document is inserted. Probably not a very good idea. If this functions fails the document will retain its old content.
See also hw_DocumentAttributes(), hw_DocumentSize(), hw_DocumentContent().
int hw_documentsize
(int hw_document);Returns the size in bytes of the document.
See also hw_DocumentBodyTag(), hw_DocumentAttributes().
string hw_errormsg
(int connection);Returns a string containing the last error message or 'No Error'. If false is returned, this function failed. The message relates to the last command.
int hw_edittext
(int connection, int hw_document);Uploads the text document to the server. The object record of the document may not be modified while the document is edited. This function will only works for pure text documents. It will not open a special data connection and therefore blocks the control connection during the transfer.
See also hw_PipeDocument(), hw_FreeDocument(), hw_DocumentBodyTag(), hw_DocumentSize(), hw_OutputDocument(), hw_GetText().
int hw_error
(int connection);Returns the last error number. If the return value is 0 no error has occurred. The error relates to the last command.
int hw_free_document
(int hw_document);Frees the memory occupied by the Hyperwave document.
array hw_getparentsobj
(int connection, int objectID);Returns an indexed array of object ids. Each object id belongs to a parent of the object with ID objectID.
array hw_getparentsobj
(int connection, int objectID);Returns an indexed array of object records plus an associated array with statistical information about the object records. The associated array is the last entry of the returned array. Each object record belongs to a parent of the object with ID objectID.
array hw_getchildcoll
(int connection, int objectID);Returns an array of object ids. Each object ID belongs to a child collection of the collection with ID objectID. The function will not return child documents.
See also hw_GetChildren(), hw_GetChildDocColl().
array hw_getchildcollobj
(int connection, int objectID);Returns an array of object records. Each object records belongs to a child collection of the collection with ID objectID. The function will not return child documents.
See also hw_ChildrenObj(), hw_GetChildDocCollObj().
int hw_getremote
(int connection, int objectID);Returns a remote document. Remote documents in Hyperwave notation are documents retrieved from an external source. Common remote documents are for example external web pages or queries in a database. In order to be able to access external sources throught remote documents Hyperwave introduces the HGI (Hyperwave Gateway Interface) which is similar to the CGI. Currently, only ftp, http-servers and some databases can be accessed by the HGI. Calling hw_GetRemote() returns the document from the external source. If you want to use this function you should be very familiar with HGIs. You should also consider to use PHP instead of Hyperwave to access external sources. Adding database support by a Hyperwave gateway should be more difficult than doing it in PHP.
See also hw_GetRemoteChildren().
int hw_getremotechildren
(int connection, string object record);Returns the children of a remote document. Children of a remote document are remote documents itself. This makes sense if a database query has to be narrowed and is explained in Hyperwave Programmers' Guide. If the number of children is 1 the function will return the document itself formated by the Hyperwave Gateway Interface (HGI). If the number of children is greater than 1 it will return an array of object record with each maybe the input value for another call to hw_GetRemoteChildren(). Those object records are virtual and do not exist in the Hyperwave server, therefore they do not have a valid object ID. How exactely such an object record looks like is up to the HGI. If you want to use this function you should be very familiar with HGIs. You should also consider to use PHP instead of Hyperwave to access external sources. Adding database support by a Hyperwave gateway should be more difficult than doing it in PHP.
See also hw_GetRemote().
array hw_getsrcbydestobj
(int connection, int objectID);Returns the object records of all anchors pointing to the object with ID objectID. The object can either be a document or an anchor of type destination.
See also hw_GetAnchors().
array hw_getobject
(int connection, [int|array] objectID, string query);Returns the object record for the object with ID objectID if the second parameter is an integer. If the second parameter is an array of integer the function will return an array of object records. In such a case the last parameter is also evaluated which is a query string.
The query string has the following syntax:
<expr> ::= "(" <expr> ")" |
"!" <expr> | /* NOT */
<expr> "||" <expr> | /* OR */
<expr> "&&" <expr> | /* AND */
<attribute> <operator> <value>
<attribute> ::= /* any attribute name (Title, Author, DocumentType ...) */
<operator> ::= "=" | /* equal */
"<" | /* less than (string compare) */
">" | /* greater than (string compare) */
"~" /* regular expression matching */
The query allows to further select certain objects from the list of given objects. Unlike the other query functions, this query may use not indexed attributes. How many object records are returned depends on the query and if access to the object is allowed.
See also hw_GetAndLock(), hw_GetObjectByQuery().
string hw_getandlock
(int connection, int objectID);Returns the object record for the object with ID objectID. It will also lock the object, so other users cannot access it until it is unlocked.
See also hw_Unlock(), hw_GetObject().
int hw_gettext
(int connection, int objectID, mixed
[rootID/prefix]
);Returns the document with object ID objectID. If the document has anchors which can be inserted, they will be inserted already. The optional parameter rootID/prefix can be a string or an integer. If it is an integer it determines how links are inserted into the document. The default is 0 and will result in links that are constructed from the name of the link's destination object. This is useful for web applications. If a link points to an object with name 'internet_movie' the HTML link will be <A HREF="/internet_movie">. The actual location of the source and destination object in the document hierachy is disregarded. You will have to set up your web browser, to rewrite that URL to for example '/my_script.php3/internet_movie'. 'my_script.php3' will have to evaluate $PATH_INFO and retrieve the document. All links will have the prefix '/my_script.php3/'. If you do not want this you can set the optional parameter rootID/prefix to any prefix which is used instead. Is this case it has to be a string.
If rootID/prefix is an integer and unequal to 0 the link is constructed from all the names starting at the object with the id rootID/prefix separated by a slash relative to the current object. If for example the above document 'internet_movie' is located at 'a-b-c-internet_movie' with '-' being the seperator between hierachy levels on the Hyperwave server and the source document is located at 'a-b-d-source' the resulting HTML link would be: <A HREF="../c/internet_movie">. This is useful if you want to download the whole server content onto disk and map the document hierachy onto the file system.
This function will only work for pure text documents. It will not open a special data connection and therefore blocks the control connection during the transfer.
See also hw_PipeDocument(), hw_FreeDocument(), hw_DocumentBodyTag(), hw_DocumentSize(), hw_OutputDocument().
array hw_getobjectbyquery
(int connection, string query, int max_hits);Searches for objects on the whole server and returns an array of object ids. The maximum number of matches is limited to max_hits. If max_hits is set to -1 the maximum number of matches is unlimited.
The query will only work with indexed attributes.
See also hw_GetObjectByQueryObj().
array hw_getobjectbyqueryobj
(int connection, string query, int max_hits);Searches for objects on the whole server and returns an array of object records. The maximum number of matches is limited to max_hits. If max_hits is set to -1 the maximum number of matches is unlimited.
The query will only work with indexed attributes.
See also hw_GetObjectByQuery().
array hw_getobjectbyquerycoll
(int connection, int objectID, string query, int max_hits);Searches for objects in collection with ID objectID and returns an array of object ids. The maximum number of matches is limited to max_hits. If max_hits is set to -1 the maximum number of matches is unlimited.
The query will only work with indexed attributes.
See also hw_GetObjectByQueryCollObj().
array hw_getobjectbyquerycollobj
(int connection, int objectID, string query, int max_hits);Searches for objects in collection with ID objectID and returns an array of object records. The maximum number of matches is limited to max_hits. If max_hits is set to -1 the maximum number of matches is unlimited.
The query will only work with indexed attributes.
See also hw_GetObjectByQueryColl().
array hw_getchilddoccoll
(int connection, int objectID);Returns array of object ids for child documents of a collection.
See also hw_GetChildren(), hw_GetChildColl().
array hw_getchilddoccollobj
(int connection, int objectID);Returns an array of object records for child documents of a collection.
See also hw_ChildrenObj(), hw_GetChildCollObj().
array hw_getanchors
(int connection, int objectID);Returns an array of object ids with anchors of the document with object ID objectID.
array hw_getanchorsobj
(int connection, int objectID);Returns an array of object records with anchors of the document with object ID objectID.
int hw_mv
(int connection, array object id array, int source id, int destination id);Moves the objects with object ids as specified in the second parameter from the collection with id source id to the collection with the id destination id. If the destination id is 0 the objects will be unlinked from the source collection. If this is the last instance of that object it will be deleted. If you want to delete all instances at once, use hw_deleteobject().
The value return is the number of moved objects.
See also hw_cp(), hw_deleteobject().
int hw_identify
(string username, string password);Identifies as user with username and password. Identification is only valid for the current session. I do not thing this function will be needed very often. In most cases it will be easier to identify with the opening of the connection.
See also hw_Connect().
array hw_incollections
(int connection, array object_id_array, array collection_id_array, int return_collections);Checks whether a set of objects (documents or collections) specified by the object_id_array is part of the collections listed in collection_id_array. When the fourth parameter return_collections is 0, the subset of object ids that is part of the collections (i.e., the documents or collections that are children of one or more collections of collection ids or their subcollections, recursively) is returned as an array. When the fourth parameter is 1, however, the set of collections that have one or more objects of this subset as children are returned as an array. This option allows a client to, e.g., highlight the part of the collection hierarchy that contains the matches of a previous query, in a graphical overview.
string hw_info
(int connection);Returns information about the current connection. The returned string has the following format: <Serverstring>, <Host>, <Port>, <Username>, <Port of Client>, <Byte swapping>
int hw_inscoll
(int connection, int objectID, array object_array);Inserts a new collection with attributes as in object_array into collection with object ID objectID.
int hw_insdoc
(int connection, int parentID, string object_record, string text);Inserts a new document with attributes as in object_record into collection with object ID parentID. This function inserts either an object record only or an object record and a pure ascii text in text if text is given. If you want to insert a general document of any kind use hw_insertdocument() instead.
See also hw_InsertDocument(), hw_InsColl().
int hw_insertdocument
(int connection, int parent_id, int hw_document);Uploads a document into the collection with parent_id. The document has to be created before with hw_NewDocument(). Make sure that the object record of the new document contains at least the attributes: Type, DocumentType, Title and Name. Possibly you also want to set the MimeType. The functions returns the object id of the new document or false.
See also hw_PipeDocument().
int hw_insertobject
(int connection, string object rec, string parameter);Inserts an object into the server. The object can be any valid hyperwave object. See the HG-CSP documentation for a detailed information on how the parameters have to be.
Note: If you want to insert an Anchor, the attribute Position has always been set either to a start/end value or to 'invisible'. Invisible positions are needed if the annotation has no correspondig link in the annotation text.
See also hw_PipeDocument(), hw_InsertDocument(), hw_InsDoc(), hw_InsColl().
int hw_modifyobject
(int connection, int object_to_change, array remove, array add, int mode);This command allows to remove, add, or modify individual attributes of an object record. The object is specified by the Object ID object_to_change. The first array remove is a list of attributes to remove. The second array add is a list of attributes to add. In order to modify an attribute one will have to remove the old one and add a new one. hw_modifyobject() will always remove the attributes before it adds attributes unless the value of the attribute to remove is not a string or array.
The last parameter determines if the modification is performed recursively. 1 means recurive modification. If some of the objects cannot be modified they will be skiped without notice. hw_error() may not indicate an error though some of the objects could not be modified.
The keys of both arrays are the attributes name. The value of each array element can either be an array, a string or anything else. If it is an array each attribute value is constructed by the key of each element plus a colon and the value of each element. If it is a string it is taken as the attribute value. An empty string will result in a complete removal of that attribute. If the value is neither a string nor an array but something else, e.g. an integer, no operation at all will be performed on the attribute. This is neccessary if you want to to add a completely new attribute not just a new value for an existing attribute. If the remove array contained an empty string for that attribute, the attribute would be tried to be removed which would fail since it doesn't exist. The following addition of a new value for that attribute would also fail. Setting the value for that attribute to e.g. 0 would not even try to remove it and the addition will work.
If you would like to change the attribute 'Name' with the current value 'books' into 'articles' you will have to create two arrays and call hw_modifyobject().
Example 1. modifying an attribute // $connect is an existing connection to the Hyperwave server // $objid is the ID of the object to modify $remarr = array("Name" => "books"); $addarr = array("Name" => "articles"); $hw_modifyobject($connect, $objid, $remarr, $addarr); |
Example 2. adding a completely new attribute // $connect is an existing connection to the Hyperwave server // $objid is the ID of the object to modify $remarr = array("Name" => 0); $addarr = array("Name" => "articles"); $hw_modifyobject($connect, $objid, $remarr, $addarr); |
Note: Multilingual attributes, e.g. 'Title', can be modified in two ways. Either by providing the attributes value in its native form 'language':'title' or by providing an array with elements for each language as described above. The above example would than be:
Example 3. modifying Title attribute $remarr = array("Title" => "en:Books"); $addarr = array("Title" => "en:Articles"); $hw_modifyobject($connect, $objid, $remarr, $addarr); |
Example 4. modifying Title attribute $remarr = array("Title" => array("en" => "Books")); $addarr = array("Title" => array("en" => "Articles", "ge"=>"Artikel")); $hw_modifyobject($connect, $objid, $remarr, $addarr); |
Example 5. removing attribute $remarr = array("Title" => ""); $addarr = array("Title" => "en:Articles"); $hw_modifyobject($connect, $objid, $remarr, $addarr); |
Note: This will remove all attributes with the name 'Title' and adds a new 'Title' attribute. This comes in handy if you want to remove attributes recursively.
Note: If you need to delete all attributes with a certain name you will have to pass an empty string as the attribute value.
Note: Only the attributes 'Title', 'Description' and 'Keyword' will properly handle the language prefix. If those attributes don't carry a language prefix, the prefix 'xx' will be assigned.
Note: The 'Name' attribute is somewhat special. In some cases it cannot be complete removed. You will get an error message 'Change of base attribute' (not clear when this happens). Therefore you will always have to add a new Name first and than remove the old one.
Note: You may not suround this function by calls to hw_getandlock() and hw_unlock(). hw_modifyobject() does this internally.
Returns TRUE if no error occurs otherwise FALSE.
int hw_new_document
(string object_record, string document_data, int document_size);Returns a new Hyperwave document with document data set to document_data and object record set to object_record. The length of the document_data has to passed in document_sizeThis function does not insert the document into the Hyperwave server.
See also hw_FreeDocument(), hw_DocumentSize(), hw_DocumentBodyTag(), hw_OutputDocument(), hw_InsertDocument().
array hw_objrec2array
(string object_record);Converts an object_record into an object array. The keys of the resulting array are the attributes names. Multiple attributes like 'Title' in different languages form its own array. The keys of this array are the left part to the colon of the attribute value. Currently only the attributes 'Title', 'Description' and 'Keyword' are treated properly.
int hw_pconnect
(string host, int port, string username, string password);Returns a connection index on success, or false if the connection could not be made. Opens a persistent connection to a Hyperwave server. Each of the arguments should be a quoted string, except for the port number. The username and password arguments are optional and can be left out. In such a case no identification with the server will be done. It is similar to identify as user anonymous. This function returns a connection index that is needed by other Hyperwave functions. You can have multiple persistent connections open at once.
See also hw_Connect().
int hw_pipedocument
(int connection, int objectID);Returns the Hyperwave document with object ID objectID. If the document has anchors which can be inserted, they will have been inserted already. The document will be transfered via a special data connection which does not block the control connection.
See also hw_GetText() for more on link insertion, hw_FreeDocument(), hw_DocumentSize(), hw_DocumentBodyTag(), hw_OutputDocument().
int hw_root
();Returns the object ID of the hyperroot collection. Currently this is always 0. The child collection of the hyperroot is the root collection of the connected server.
int hw_unlock
(int connection, int objectID);Unlocks a document, so other users regain access.
See also hw_GetAndLock().
int hw_who
(int connection);Returns an array of users currently logged into the Hyperwave server. Each entry in this array is an array itself containing the elements id, name, system, onSinceDate, onSinceTime, TotalTime and self. 'self' is 1 if this entry belongs to the user who initianted the request.
To get these functions to work, you have to compile PHP with --with-icap. That requires the icap library to be installed. Grab the latest version from http://icap.chek.com/ and compile and install it.
stream icap_open
(stringcalendar, stringusername, stringpassword, stringoptions);Returns an ICAP stream on success, false on error.
icap_open() opens up an ICAP connection to the specified calendar store. If the optional options is specified, passes the options to that mailbox also.
objecticap_fetch_event
(streamicap_stream, idevent id, optionsoptions);icap_fetch_event() fetches an event from the calendar stream specified by id.
Returns an event object consisting of:
int id - ID of that event.
int public - TRUE if the event if public, FALSE if it is private.
string category - Category string of the event.
string title - Title string of the event.
string description - Description string of the event.
int alarm - number of minutes before the event to send an alarm/reminder.
object start - Object containing a datetime entry.
object end - Object containing a datetime entry.
int year - year
int month - month
int mday - day of month
int hour - hour
int min - minutes
int sec - seconds
array icap_list_events
(stream icap_stream, datetime begin_date, datetime end_date);Returns an array of event ID's that are between the two given datetimes.
icap_list_events() function takes in a beginning datetime and an end datetime for a calendar stream. An array of event id's that are between the given datetimes are returned.
All datetime entries consist of an object that contains:
int year - year
int month - month
int mday - day of month
int hour - hour
int min - minutes
int sec - seconds
int icap_store_event
(int icap_stream, object event);icap_store_event() Stores an event into an ICAP calendar. an event object consists of:
int public - 1 if public, 0 if private;
string caegory - Category string of the event.
string title - Title string of the event.
string description - Description string of the event.
int alarm - Number of minutes before the event to sned out an alarm.
datetime start - datetime object of the start of the event.
datetime end - datetime object of the end of the event.
All datetime entries consist of an object that contains:
int year - year
int month - month
int mday - day of month
int hour - hour
int min - minutes
int sec - seconds
Returns true on success and false on error.
int icap_delete_event
(int uid);icap_delete_event() deletes the calendar event specified by the uid.
Returns true.
int icap_snooze
(int uid);icap_snooze() turns off an alarm for a calendar event specified by the uid.
Returns true.
array icap_list_alarms
(stream icap_stream, datetime alarm_date);Returns an array of event ID's that has an alarm going off at the given datetime.
icap_list_alarms() function takes in a datetime for a calendar stream. An array of event id's that has an alarm should be going off at the datetime are returned.
All datetime entries consist of an object that contains:
int year - year
int month - month
int mday - day of month
int hour - hour
int min - minutes
int sec - seconds
You can use the image functions in PHP to get the size of JPEG, GIF, and PNG images, and if you have the GD library (available at http://www.boutell.com/gd/) you will also be able to create and manipulate images.
array getimagesize
(string filename, array [imageinfo]);The GetImageSize() function will determine the size of any GIF, JPG or PNG image file and return the dimensions along with the file type and a height/width text string to be used inside a normal HTML IMG tag.
Returns an array with 4 elements. Index 0 contains the width of the image in pixels. Index 1 contains the height. Index 2 a flag indicating the type of the image. 1 = GIF, 2 = JPG, 3 = PNG. Index 3 is a text string with the correct "height=xxx width=xxx" string that can be used directly in an IMG tag.
Example 1. GetImageSize <?php $size = GetImageSize("img/flag.jpg"); ?> <IMG SRC="img/flag.jpg" <?php echo $size[3]; ?>> |
The optional imageinfo parameter allows you to extract some extended information from the image file. Currently this will return the diffrent JPG APP markers in an associative Array. Some Programs use these APP markers to embedd text information in images. A very common one in to embed IPTC http://www.xe.net/iptc/ information in the APP13 marker. You can use the iptcparse() function to parse the binary APP13 marker into something readable.
Example 2. GetImageSize returning IPTC <?php $size = GetImageSize("testimg.jpg",&$info); if (isset($info["APP13"])) { $iptc = iptcparse($info["APP13"]); var_dump($iptc); } ?> |
Note: This function does not require the GD image library.
int imagearc
(int im, int cx, int cy, int w, int h, int s, int e, int col);ImageArc draws a partial ellipse centered at cx, cy (top left is 0,0) in the image represented by im. w and h specifies the ellipse's width and height respectively while the start and end points are specified in degrees indicated by the s and e arguments.
int imagechar
(int im, int font, int x, int y, string c, int col);ImageChar draws the first character of c in the image identified by id with its upper-left at x,y (top left is 0,0) with the color col. If font is 1, 2, 3, 4 or 5, a built-in font is used (with higher numbers corresponding to larger fonts).
See also imageloadfont().
int imagecharup
(int im, int font, int x, int y, string c, int col);ImageCharUp draws the character c vertically in the image identified by im at coordinates x, y (top left is 0, 0) with the color col. If font is 1, 2, 3, 4 or 5, a built-in font is used.
See also imageloadfont().
int imagecolorallocate
(int im, int red, int green, int blue);ImageColorAllocate returns a color identifier representing the color composed of the given RGB components. The im argument is the return from the imagecreate() function. ImageColorAllocate must be called to create each color that is to be used in the image represented by im.
$white = ImageColorAllocate($im, 255,255,255); $black = ImageColorAllocate($im, 0,0,0);
int imagecolortransparent
(int im, int [col]);ImageColorTransparent sets the transparent color in the im image to col. im is the image identifier returned by imagecreate() and col is a color identifier returned by imagecolorallocate().
The identifier of the new (or current, if none is specified) transparent color is returned.
int imagecopyresized
(int dst_im, int src_im, int dstX, int dstY, int srcX, int srcY, int dstW, int dstH, int srcW, int srcH);ImageCopyResized copies a rectangular portion of one image to another image. dst_im is the destination image, src_im is the source image identifier. If the source and destination coordinates and width and heights differ, appropriate stretching or shrinking of the image fragment will be performed. The coordinates refer to the upper left corner. This function can be used to copy regions within the same image (if dst_im is the same as src_im) but if the regions overlap the results will be unpredictable.
int imagecreate
(int x_size, int y_size);ImageCreate returns an image identifier representing a blank image of size x_size by y_size.
int imagecreatefromgif
(string filename);imagecreatefromgif() returns an image identifier representing the image obtained from the given filename.
imagecreatefromgif() returns an empty string on failure. It also outputs an error message, which unfortunately displays as a broken link in a browser. To ease debugging the following example will produce an error GIF:
Example 1. Example to handle an error during creation (courtesy vic@zymsys.com ) function LoadGif($imgname) { $im = @imagecreatefromgif($imgname); /* Attempt to open */ if ($im == "") { /* See if it failed */ $im = ImageCreate(150,30); /* Create a blank image */ $bgc = ImageColorAllocate($im,255,255,255); $tc = ImageColorAllocate($im,0,0,0); ImageFilledRectangle($im,0,0,150,30,$bgc); ImageString($im,1,5,5,"Error loading $imgname",$tc); /* Output an errmsg */ } return $im; } |
Note: Since all GIF support was removed from the GD library in version 1.6, this function is not available if you are using that version of the GD library.
int imagedashedline
(int im, int x1, int y1, int x2, int y2, int col);ImageLine draws a dashed line from x1,y1 to x2,y2 (top left is 0,0) in image im of color col.
See also imageline().
int imagedestroy
(int im);ImageDestroy frees any memory associated with image im. im is the image identifier returned by the imagecreate() function.
int imagefill
(int im, int x, int y, int col);ImageFill performs a flood fill starting at coordinate x, y (top left is 0,0) with color col in the image im.
int imagefilledpolygon
(int im, array points, int num_points, int col);ImageFilledPolygon creates a filled polygon in image im. points is a PHP array containing the polygon's vertices, ie. points[0] = x0, points[1] = y0, points[2] = x1, points[3] = y1, etc. num_points is the total number of vertices.
int imagefilledrectangle
(int im, int x1, int y1, int x2, int y2, int col);ImageFilledRectangle creates a filled rectangle of color col in image im starting at upper left coordinates x1, y1 and ending at bottom right coordinates x2, y2. 0, 0 is the top left corner of the image.
int imagefilltoborder
(int im, int x, int y, int border, int col);ImageFillToBorder performs a flood fill whose border color is defined by border. The starting point for the fill is x,y (top left is 0,0) and the region is filled with color col.
int imagefontheight
(int font);Returns the pixel height of a character in the specified font.
See also imagefontwidth() and imageloadfont().
int imagefontwidth
(int font);Returns the pixel width of a character in font.
See also imagefontheight() and imageloadfont().
int imagegif
(int im, string filename);imagegif() creates the GIF file in filename from the image im. The im argument is the return from the imagecreate() function.
The image format will be GIF87a unless the image has been made transparent with imagecolortransparent(), in which case the image format will be GIF89a.
The filename argument is optional, and if left off, the raw image stream will be output directly. By sending an image/gif content-type using header(), you can create a PHP script that outputs GIF images directly.
Note: Since all GIF support was removed from the GD library in version 1.6, this function is not available if you are using that version of the GD library.
int imageinterlace
(int im, int [interlace]);ImageInterlace() turns the interlace bit on or off. If interlace is 1 the im image will be interlaced, and if interlace is 0 the interlace bit is turned off.
This functions returns whether the interlace bit is set for the image.
int imageline
(int im, int x1, int y1, int x2, int y2, int col);ImageLine draws a line from x1,y1 to x2,y2 (top left is 0,0) in image im of color col.
See also imagecreate() and imagecolorallocate().
int imageloadfont
(string file);ImageLoadFont loads a user-defined bitmap font and returns an identifier for the font (that is always greater than 5, so it will not conflict with the built-in fonts).
The font file format is currently binary and architecture dependent. This means you should generate the font files on the same type of CPU as the machine you are running PHP on.
Table 1. Font file format
byte position | C data type | description |
---|---|---|
byte 0-3 | int | number of characters in the font |
byte 4-7 | int | value of first character in the font (often 32 for space) |
byte 8-11 | int | pixel width of each character |
byte 12-15 | int | pixel height of each character |
byte 16- | char | array with character data, one byte per pixel in each character, for a total of (nchars*width*height) bytes. |
See also ImageFontWidth() and ImageFontHeight().
int imagepolygon
(int im, array points, int num_points, int col);ImagePolygon creates a polygon in image id. points is a PHP array containing the polygon's vertices, ie. points[0] = x0, points[1] = y0, points[2] = x1, points[3] = y1, etc. num_points is the total number of vertices.
See also imagecreate().
int imagerectangle
(int im, int x1, int y1, int x2, int y2, int col);ImageRectangle creates a rectangle of color col in image im starting at upper left coordinate x1,y1 and ending at bottom right coordinate x2,y2. 0,0 is the top left corner of the image.
int imagesetpixel
(int im, int x, int y, int col);ImageSetPixel draws a pixel at x,y (top left is 0,0) in image im of color col.
See also imagecreate() and imagecolorallocate().
int imagestring
(int im, int font, int x, int y, string s, int col);ImageString draws the string s in the image identified by im at coordinates x,y (top left is 0,0) in color col. If font is 1, 2, 3, 4 or 5, a built-in font is used.
See also imageloadfont().
int imagestringup
(int im, int font, int x, int y, string s, int col);ImageStringUp draws the string s vertically in the image identified by im at coordinates x,y (top left is 0,0) in color col. If font is 1, 2, 3, 4 or 5, a built-in font is used.
See also imageloadfont().
int imagesx
(int im);ImageSX returns the width of the image identified by im.
See also imagecreate() and imagesy().
int imagesy
(int im);ImageSY returns the height of the image identified by im.
See also imagecreate() and imagesx().
array ImageTTFBBox
(int size, int angle, string fontfile, string text);This function calculates and returns the bounding box in pixels a TrueType text.
The string to be measured.
The font size.
The name of the TrueType font file. (Can also be an URL.)
Angle in degrees in which text will be measured.
0 | lower left corner, X position |
1 | lower left corner, Y position |
2 | lower right corner, X position |
3 | lower right corner, Y position |
4 | upper right corner, X position |
5 | upper right corner, Y position |
6 | upper left corner, X position |
7 | upper left corner, Y position |
This function requires both the GD library and the Freetype library.
See also ImageTTFText().
array ImageTTFText
(int im, int size, int angle, int x, int y, int col, string fontfile, string text);ImageTTFText draws the string text in the image identified by im, starting at coordinates x,y (top left is 0,0), at an angle of angle in color col, using the TrueType font file identified by fontfile.
The coordinates given by x,y will define the basepoint of the first character (roughly the lower-left corner of the character). This is different from the ImageString(), where x,y define the upper-right corner of the first character.
angle is in degrees, with 0 degrees being left-to-right reading text (3 o'clock direction), and higher values representing a counter-clockwise rotation. (i.e., a value of 90 would result in bottom-to-top reading text).
fontfile is the path to the TrueType font you wish to use.
text is the text string which may include UTF-8 character sequences (of the form: { ) to access characters in a font beyond the first 255.
col is the color index. Using the negative of a color index has the effect of turning off antialiasing.
ImageTTFText() returns an array with 8 elements representing four points making the bounding box of the text. The order of the points is upper left, upper right, lower right, lower left. The points are relative to the text regardless of the angle, so "upper left" means in the top left-hand corner when you see the text horizontallty.
This example script will produce a black GIF 400x30 pixels, with the words "Testing..." in white in the font Arial.
Example 1. ImageTTFText <?php Header("Content-type: image/gif"); $im = imagecreate(400,30); $black = ImageColorAllocate($im, 0,0,0); $white = ImageColorAllocate($im, 255,255,255); ImageTTFText($im, 20, 0, 10, 20, $white, "/path/arial.ttf", "Testing... Omega: Ω"); ImageGif($im); ImageDestroy($im); ?> |
This function requires both the GD library and the FreeType library.
See also ImageTTFBBox().
int imagecolorat
(int im, int x, int y);Returns the index of the color of the pixel at the specified location in the image.
See also imagecolorset() and imagecolorsforindex().
int imagecolorclosest
(int im, int red, int green, int blue);Returns the index of the color in the palette of the image which is "closest" to the specified RGB value.
The "distance" between the desired color and each color in the palette is calculated as if the RGB values represented points in three-dimensional space.
See also imagecolorexact().
int imagecolorexact
(int im, int red, int green, int blue);Returns the index of the specified color in the palette of the image.
If the color does not exist in the image's palette, -1 is returned.
See also imagecolorclosest().
int imagecolorresolve
(int im, int red, int green, int blue);This function is guaranteed to return a color index for a requested color, either the exact color or the closest possible alternative.
See also imagecolorclosest().
bool imagecolorset
(int im, int index, int red, int green, int blue);This sets the specified index in the palette to the specified color. This is useful for creating flood-fill-like effects in paletted images without the overhead of performing the actual flood-fill.
See also imagecolorat().
array imagecolorsforindex
(int im, int index);This returns an associative array with red, green, and blue keys that contain the appropriate values for the specified color index.
See also imagecolorat() and imagecolorexact().
int imagecolorstotal
(int im);This returns the number of colors in the specified image's palette.
See also imagecolorat() and imagecolorsforindex().
int imagepsloadfont
(string filename);In the case everything went right, a valid font index will be returned and can be used for further purposes. Otherwise the function returns false and prints a message describing what went wrong.
See also imagepsfreefont().
int imagepsencodefont
(string encodingfile);Loads a character encoding vector from from a file and changes the fonts encoding vector to it. As a PostScript fonts default vector lacks most of the character positions above 127, you'll definitely want to change this if you use an other language than english. The exact format of this file is described in T1libs documentation. T1lib comes with two ready-to-use files, IsoLatin1.enc and IsoLatin2.enc.
If you find yourself using this function all the time, a much better way to define the encoding is to set ps.default_encoding in the configuration file to point to the right encoding file and all fonts you load will automatically have the right encoding.
array imagepstext
(int image, string text, int font, int size, int foreground, int background, int x, int y, int [space], int [tightness], float [angle], int [antialias_steps]);size is expressed in pixels.
foreground is the color in which the text will be painted. background is the color to which the text will try to fade in with antialiasing. No pixels with the color background are actually painted, so the background image does not need to be of solid color.
The coordinates given by x, y will define the origin (or reference point) of the first character (roughly the lower-left corner of the character). This is different from the ImageString(), where x, y define the upper-right corner of the first character. Refer to PostScipt documentation about fonts and their measuring system if you have trouble understanding how this works.
space allows you to change the default value of a space in a font. This amount is added to the normal value and can also be negative.
tightness allows you to control the amount of white space between characters. This amount is added to the normal character width and can also be negative.
angle is in degrees.
antialias_steps allows you to control the number of colours used for antialiasing text. Allowed values are 4 and 16. The higher value is recommended for text sizes lower than 20, where the effect in text quality is quite visible. With bigger sizes, use 4. It's less computationally intensive.
Parameters space and tightness are expressed in character space units, where 1 unit is 1/1000th of an em-square.
Parameters space, tightness, angle and antialias are optional.
This function returns an array containing the following elements:
0 | lower left x-coordinate |
1 | lower left y-coordinate |
2 | upper right x-coordinate |
3 | upper right y-coordinate |
See also imagepsbbox().
array imagepsbbox
(string text, int font, int size, int space, int width, float angle);size is expressed in pixels.
space allows you to change the default value of a space in a font. This amount is added to the normal value and can also be negative.
tightness allows you to control the amount of white space between characters. This amount is added to the normal character width and can also be negative.
angle is in degrees.
Parameters space and tightness are expressed in character space units, where 1 unit is 1/1000th of an em-square.
Parameters space, tightness and angle are optional.
The bounding box is calculated using information available from character metrics, and unfortunately tends to differ slightly from the results achieved by actually rasterizing the text. If the angle is 0 degrees, you can expect the text to need 1 pixel more to every direction.
This function returns an array containing the following elements:
0 | lower left x-coordinate |
1 | lower left y-coordinate |
2 | upper right x-coordinate |
3 | upper right y-coordinate |
See also imagepstext().
To get these functions to work, you have to compile PHP with --with-imap. That requires the c-client library to be installed. Grab the latest version from ftp://ftp.cac.washington.edu/imap/ and compile it. Then copy c-client/c-client.a to /usr/local/lib or some other directory on your link path and copy c-client/rfc822.h, mail.h and linkage.h to /usr/local/include or some other directory in your include path.
int imap_append
(int imap_stream, string mbox, string message, stringflags);Returns true on sucess, false on error.
imap_append() appends a string message to the specified mailbox mbox. If the optional flags is specified, writes the flags to that mailbox also.
When talking to the Cyrus IMAP server, you must use "\r\n" as your end-of-line terminator instead of "\n" or the operation will fail.
string imap_base64
(string text);imap_base64() function decodes BASE-64 encoded text. The decoded message is returned as a string.
string imap_body
(int imap_stream, int msg_number, int flags);imap_body() returns the body of the message, numbered msg_number in the current mailbox. The optional flags are a bit mask with one or more of the following:
FT_UID - The msgno is a UID
FT_PEEK - Do not set the \Seen flag if not already set
FT_INTERNAL - The return string is in internal format, will not canonicalize to CRLF.
array imap_check
(int imap_stream);Returns information about the current mailbox. Returns FALSE on failure.
The imap_check() function checks the current mailbox status on the server and returns the information in an object with following properties.
Date : date of the message
Driver : driver
Mailbox : name of the mailbox
Nmsgs : number of messages
Recent : number of recent messages
int imap_close
(int imap_stream, int flags);Close the imap stream. Takes an optional flag CL_EXPUNGE, which will silently expunge the mailbox before closing.
int imap_createmailbox
(int imap_stream, string mbox);imap_createmailbox() creates a new mailbox specified by mbox.
Returns true on success and false on error.
int imap_delete
(int imap_stream, int msg_number);Returns true.
imap_delete() function marks message pointed by msg_number for deletion. Actual deletion of the messages is done by imap_expunge().
int imap_deletemailbox
(int imap_stream, string mbox);imap_deletemailbox() deletes the specified mailbox.
Returns true on success and false on error.
int imap_expunge
(int imap_stream);imap_expunge() deletes all the messages marked for deletion by imap_delete().
Returns true.
string imap_fetchbody
(int imap_stream, int msg_number, string part_number, flags flags);This function causes a fetch of a particular section of the body of the specified messages as a text string and returns that text string. The section specification is a string of integers delimited by period which index into a body part list as per the IMAP4 specification. Body parts are not decoded by this function.
The options for imap_fetchbody ()e a bitmask with one or more of the following
FT_UID - The msgono is a UID
FT_PEEK - Do not set the \Seen flag if not already set
FT_UID - The return string is in "internal" format, without any attempt to canonicalize CRLF
array imap_fetchstructure
(int imap_stream, int msg_number);This function causes a fetch of all the structured information for the given msg_number. The returned value is an object with following elements.
type, encoding, ifsubtype, subtype, ifdescription, description, ifid,
id, lines, bytes, ifparameters
It also returns an array of objects called parameters[]. This object has following properties.
attribute, value
object imap_header
(int imap_stream, int msg_number, int fromlength, int subjectlength, int defaulthost);This function returns an object of various header elements
remail,date,Date,subject,Subject,in_reply_to,message_id,newsgroups,
followup_to,references
message flags:
Recent - 'R' if recent and seen, 'N' if recent and not seen, ' ' if not recent
Unseen - 'U' if not seen AND not recent, ' ' if seen OR not seen and recent
Answered - 'A' if answered, ' ' if unanswered
Deleted - 'D' if deleted, ' ' if not deleted
Draft - 'X' if draft, ' ' if not draft
Flagged - 'F' if flagged, ' ' if not flagged
NOTE that the Recent/Unseen behavior is a little odd. If you want to know if a message is Unseen, you must check for
Unseen == 'U' || Recent == 'N'
toaddress (full to: line, up to 1024 characters)
to[] (returns an array of objects from the To line, containing:)
personal
adl
mailbox
host
fromaddress (full from: line, up to 1024 characters)
from[] (returns an array of objects from the From line, containing:)
personal
adl
mailbox
host
ccaddress (full cc: line, up to 1024 characters)
cc[] (returns an array of objects from the Cc line, containing:)
personal
adl
mailbox
host
bccaddress (full bcc line, up to 1024 characters)
bcc[] (returns an array of objects from the Bcc line, containing:)
personal
adl
mailbox
host
reply_toaddress (full reply_to: line, up to 1024 characters)
reply_to[] (returns an array of objects from the Reply_to line, containing:)
personal
adl
mailbox
host
senderaddress (full sender: line, up to 1024 characters)
sender[] (returns an array of objects from the sender line, containing:)
personal
adl
mailbox
host
return_path (full return-path: line, up to 1024 characters)
return_path[] (returns an array of objects from the return_path line, containing:)
personal
adl
mailbox
host
udate ( mail message date in unix time)
fetchfrom (from line formatted to fit fromlength characters)
fetchsubject (subject line formatted to fit subjectlength characters)
array imap_headers
(int imap_stream);Returns an array of string formatted with header info. One element per mail message.
array imap_listmailbox
(int imap_stream, string ref, string pat);Returns an array containing the names of the mailboxes.
array imap_getmailboxes
(int imap_stream, string ref, string pat);Returns an array of objects containing mailbox information. Each object has the attributes name, specifying the full name of the mailbox; delimiter, which is the hierarchy delimiter for the part of the hierarchy this mailbox is in; and attributes. Attributes is a bitmask that can be tested against:
LATT_NOINFERIORS - This mailbox has no "children" (there are no mailboxes below this one)
LATT_NOSELECT - This is only a container, not a mailbox - you cannot open it.
LATT_MARKED - This mailbox is marked. Only used by UW-IMAPD.
LATT_UNMARKED - This mailbox is not marked. Only used by UW-IMAPD.
ref should normally be just the IMAP server, in the form: {imap_server:imap_port}, and pattern specifies where in the mailbox hierarchy to start searching. If you want all mailboxes, pass pattern as an empty string.
There are two special characters you can pass as part of the pattern: '*' and '%'. '*' means to return all mailboxes. If you pass pattern as '*', you will get a list of the entire mailbox hierarchy. '%' means to return the current level only. '%' as the pattern parameter will return only the top level mailboxes; '~/mail/%' on UW_IMAPD will return every mailbox in the ~/mail directory, but none in subfolders of that directory.
array imap_listsubscribed
(int imap_stream, string ref, string pattern);Returns an array of all the mailboxes that you have subscribed. The ref and pattern arguments specify the base location to search from and the pattern the mailbox name must match.
array imap_getsubscribed
(int imap_stream, string ref, string pattern);This function is identical to imap_getmailboxes(), except that it only returns mailboxes that the user is subscribed to.
int imap_mail_copy
(int imap_stream, string msglist, string mbox, int flags);Returns true on success and false on error.
Copies mail messages specified by msglist to specified mailbox. msglist is a range not just message numbers.
flags is a bitmask of one or more of
CP_UID - the sequence numbers contain UIDS
CP_MOVE - Delete the messages from the current mailbox after copying
int imap_mail_move
(int imap_stream, string msglist, string mbox);Moves mail messages specified by msglist to specified mailbox. msglist is a range not just message numbers.
Returns true on success and false on error.
int imap_num_recent
(int imap_stream);Returns the number of recent messages in the current mailbox.
int imap_open
(string mailbox, string username, string password, int flags);Returns an IMAP stream on success and false on error. This function can also be used to open streams to POP3 and NNTP servers. To connect to an IMAP server running on port 143 on the local machine, do the following:
$mbox = imap_open("{localhost:143}INBOX","user_id","password");
$mbox = imap_open("{localhost/pop3:110}INBOX","user_id","password");
$nntp = imap_open("{localhost/nntp:119}comp.test","","");
The options are a bit mask with one or more of the following:
OP_READONLY - Open mailbox read-only
OP_ANONYMOUS - Dont use or update a .newsrc for news
OP_HALFOPEN - For IMAP and NNTP names, open a connection but dont open a mailbox
CL_EXPUNGE - Expunge mailbox automatically upon mailbox close
int imap_ping
(int imap_stream);Returns true if the stream is still alive, false otherwise.
imap_ping() function pings the stream to see it is still active. It may discover new mail; this is the preferred method for a periodic "new mail check" as well as a "keep alive" for servers which have inactivity timeout.
int imap_renamemailbox
(int imap_stream, string old_mbox, string new_mbox);This function renames on old mailbox to new mailbox.
Returns true on success and false on error.
int imap_reopen
(string imap_stream, string mailbox, string
[flags]);Returns true on success and false on error.
This function reopens the specified stream to new mailbox.
The options are a bit mask with one or more of the following:
OP_READONLY - Open mailbox read-only
OP_ANONYMOUS - Dont use or update a .newsrc for news
OP_HALFOPEN - For IMAP and NNTP names, open a connection but dont open a mailbox
CL_EXPUNGE - Expunge mailbox automatically upon mailbox close
int imap_subscribe
(int imap_stream, string mbox);Subscribe to a new mailbox.
Returns true on success and false on error.
int imap_undelete
(int imap_stream, int msg_number);This function removes the deletion flag for a specified message, which is set by imap_delete().
Returns true on success and false on error.
int imap_unsubscribe
(int imap_stream, string mbox);Unsubscribe from a specified mailbox.
Returns true on success and false on error.
string imap_qprint
(string string);Convert a quoted-printable string to an 8 bit string
Returns an 8 bit (binary) string
string imap_8bit
(string string);Convert an 8bit string to a quoted-printable string.
Returns a quoted-printable string
string imap_binary
(string string);Convert an 8bit string to a base64 string.
Returns a base64 string
array imap_scanmailbox
(int imap_stream, string string);Returns an array containing the names of the mailboxes that have string in the text of the mailbox.
array imap_mailboxmsginfo
(int imap_stream);Returns information about the current mailbox. Returns FALSE on failure.
The imap_mailboxmsginfo() function checks the current mailbox status on the server and returns the information in an object with following properties.
Date : date of the message
Driver : driver
Mailbox : name of the mailbox
Nmsgs : number of messages
Recent : number of recent messages
Unread : number of unread messages
Size : mailbox size
string imap_rfc822_write_address
(string mailbox, string host, string personal);Returns a properly formatted email address given the mailbox, host, and personal info.
string imap_rfc822_parse_adrlist
(string address, string default_host);This function parses the address tring and for each address, returns an array of objects. The 4 objects are:
mailbox - the mailbox name (username)
host - the host name
personal - the personal name
adl - at domain source route
string imap_setflag_full
(int stream, string sequence, string flag, string options);This function causes a store to add the specified flag to the flags set for the messages in the specified sequence.
The options are a bit mask with one or more of the following:
ST_UID The sequence argument contains UIDs instead of
sequence numbers
string imap_clearflag_full
(int stream, string sequence, string flag, string options);This function causes a store to delete the specified flag to the flags set for the messages in the specified sequence.
The options are a bit mask with one or more of the following:
ST_UID The sequence argument contains UIDs instead of
sequence numbers
string imap_sort
(int stream, int criteria, int reverse, int options);Returns an array of message numbers sorted by the given parameters
Rev is 1 for reverse-sorting.
Criteria can be one (and only one) of the following:
SORTDATE message Date
SORTARRIVAL arrival date
SORTFROM mailbox in first From address
SORTSUBJECT message Subject
SORTTO mailbox in first To address
SORTCC mailbox in first cc address
SORTSIZE size of message in octets
The flags are a bitmask of one or more of the following:
SE_UID Return UIDs instead of sequence numbers
SE_NOPREFETCH Don't prefetch searched messages.
stringimap_fetchheader
(int imap_stream, int msgno, int flags);This function causes a fetch of the complete, unfiltered RFC 822 format header of the specified message as a text string and returns that text string.
The options are:
FT_UID The msgno argument is a UID
FT_INTERNAL The return string is in "internal" format,
without any attempt to canonicalize to CRLF
newlines
FT_PREFETCHTEXT The RFC822.TEXT should be pre-fetched at the
same time. This avoids an extra RTT on an
IMAP connection if a full message text is
desired (e.g. in a "save to local file"
operation)
int imap_uid
(int imap_stream, int msgno);This function returns the UID for the given message sequence number. It is the inverse of imap_msgno().
int imap_msgno
(int imap_stream, int uid);This function returns the message sequence number for the given UID. It is the inverse of imap_uid().
array imap_search
(int imap_stream, string criteria, int flags);This function performs a search on the mailbox currently opened in the given imap stream. criteria is a string, delimited by spaces, in which the following keywords are allowed. Any multi-word arguments (eg FROM "joe smith") must be quoted.
ALL - return all messages matching the rest of the criteria
ANSWERED - match messages with the \\ANSWERED flag set
BCC "string" - match messages with "string" in the Bcc: field
BEFORE "date" - match messages with Date: before "date"
BODY "string" - match messages with "string" in the body of the message
CC "string" - match messages with "string" in the Cc: field
DELETED - match deleted messages
FLAGGED - match messages with the \\FLAGGED (sometimes referred to as Important or Urgent) flag set
FROM "string" - match messages with "string" in the From: field
KEYWORD "string" - match messages with "string" as a keyword
NEW - match new messages
OLD - match old messages
ON "date" - match messages with Date: matching "date"
RECENT - match messages with the \\RECENT flag set
SEEN - match messages that have been read (the \\SEEN flag is set)
SINCE "date" - match messages with Date: after "date"
SUBJECT "string" - match messages with "string" in the Subject:
TEXT "string" - match messages with text "string"
TO "string" - match messages with "string" in the To:
UNANSWERED - match messages that have not been answered
UNDELETED - match messages that are not deleted
UNFLAGGED - match messages that are not flagged
UNKEYWORD "string" - match messages that do not have the keyword "string"
UNSEEN - match messages which have not been read yet
For example, to match all unanswered messages sent by Mom, you'd use: "UNANSWERED FROM mom". Searches appear to be case insensitive. This list of criteria is from a reading of the UW c-client source code and may be uncomplete or inaccurate. Searcher beware.
Valid values for flags are SE_UID, which causes the returned array to contain UIDs instead of messages sequence numbers.
string imap_last_error
(void );This function returns the full text of the last IMAP error message that occurred on the current page. The error stack is untouched; calling imap_last_error() subsequently, with no intervening errors, will return the same error.
array imap_errors
(void );This function returns an array of all of the IMAP error messages generated since the last imap_errors() call, or the beginning of the page. When imap_errors() is called, the error stack is subsequently cleared.
array imap_alerts
(void );This function returns an array of all of the IMAP alert messages generated since the last imap_alerts() call, or the beginning of the page. When imap_alerts() is called, the alert stack is subsequently cleared. The IMAP specification requires that these messages be passed to the user.
object imap_status
(int imap_stream, string mailbox, int options);This function returns an object containing status information. Valid flags are:
SA_MESSAGES - set status->messages to the number of messages in the mailbox
SA_RECENT - set status->recent to the number of recent messages in the mailbox
SA_UNSEEN - set status->unseen to the number of unseen (new) messages in the mailbox
SA_UIDNEXT - set status->uidnext to the next uid to be used in the mailbox
SA_UIDVALIDITY - set status->uidvalidity to a constant that changes when uids for the mailbox may no longer be valid
SA_ALL - set all of the above
status->flags is also set, which contains a bitmask which can be checked against any of the above constants.
int error_log
(string message, int message_type, string [destination], string [extra_headers]);Sends an error message to the web server's error log, a TCP port or to a file. The first parameter, message, is the error message that should be logged. The second parameter, message_type says where the message should go:
Table 1. error_log() log types
0 | message is sent to PHP's system logger, using the Operating System's system logging mechanism or a file, depending on what the error_log configuration directive is set to. |
1 | message is sent by email to the address in the destination parameter. This is the only message type where the fourth parameter, extra_headers is used. This message type uses the same internal function as Mail() does. |
2 | message is sent through the PHP debugging connection. This option is only available if remote debugging has been enabled. In this case, the destination parameter specifies the host name or IP address and optionally, port number, of the socket receiving the debug information. |
3 | message is appended to the file destination. |
Example 1. error_log() examples // Send notification through the server log if we can not // connect to the database. if (!Ora_Logon($username, $password)) { error_log("Oracle database not available!", 0); } // Notify administrator by email if we run out of FOO if (!($foo = allocate_new_foo()) { error_log("Big trouble, we're all out of FOOs!", 1, "operator@mydomain.com"); } // other ways of calling error_log(): error_log("You messed up!", 2, "127.0.0.1:7000"); error_log("You messed up!", 2, "loghost"); error_log("You messed up!", 3, "/var/tmp/my-errors.log"); |
int error_reporting
(int [level]);Sets PHP's error reporting level and returns the old level. The error reporting level is a bitmask of the following values (follow the links for the internal values to get their meanings):
Table 1. error_reporting() bit values
value | internal name |
---|---|
1 | E_ERROR |
2 | E_WARNING |
4 | E_PARSE |
8 | E_NOTICE |
16 | E_CORE_ERROR |
32 | E_CORE_WARNING |
string getenv
(string varname);Returns the value of the environment variable varname, or false on an error.
$ip = getenv("REMOTE_ADDR"); // get the ip number of the user
You can see a list of all the environmental variables by using phpinfo(). You can find out what many of them mean by taking a look at the CGI specification, specifically the page on environmental variables.
string get_cfg_var
(string varname);Returns the current value of the PHP configuration variable specified by varname, or false if an error occurs.
It will not return configuration information set when the PHP was compiled, or read from an Apache configuration file (using the php3_configuration_option directives).
To check whether the system is using a configuration file, try retrieving the value of the cfg_file_path configuration setting. If this is available, a configuration file is being used.
string get_current_user
(void);Returns the name of the owner of the current PHP script.
See also getmyuid(), getmypid(), getmyinode(), and getlastmod().
long get_magic_quotes_gpc
(void);Returns the current active configuration setting of magic_quotes_gpc. (0 for off, 1 for on)
See also get_magic_quotes_runtime(), set_magic_quotes_runtime().
long get_magic_quotes_runtime
(void);Returns the current active configuration setting of magic_quotes_runtime. (0 for off, 1 for on)
See also get_magic_quotes_gpc(), set_magic_quotes_runtime().
int getlastmod
(void);Returns the time of the last modification of the current page. The value returned is a Unix timestamp, suitable for feeding to date(). Returns false on error.
Example 1. getlastmod() example // outputs e.g. 'Last modified: March 04 1998 20:43:59.' echo "Last modified: ".date( "F d Y H:i:s.", getlastmod() ); |
See alse date(), getmyuid(), get_current_user(), getmyinode(), and getmypid().
int getmyinode
(void);Returns the current script's inode, or false on error.
See also getmyuid(), get_current_user(), getmypid(), and getlastmod().
int getmypid
(void);Returns the current PHP process ID, or false on error.
Note that when running as a server module, separate invocations of the script are not guaranteed to have distinct pids.
See also getmyuid(), get_current_user(), getmyinode(), and getlastmod().
int getmyuid
(void);Returns the user ID of the current script, or false on error.
See also getmypid(), get_current_user(), getmyinode(), and getlastmod().
array getrusage
(int [who]);This is an interface to getrusage(2). It returns an associative array containing the data returned from the system call. If who is 1, getrusage will be called with RUSAGE_CHILDREN. All entries are accessible by using their documented field names.
Example 1. Getrusage Example $dat = getrusage(); echo $dat["ru_nswap"]; # number of swaps echo $dat["ru_majflt"]; # number of page faults echo $dat["ru_utime.tv_sec"]; # user time used (seconds) echo $dat["ru_utime.tv_usec"]; # user time used (microseconds) |
int phpinfo
(void);Outputs a large amount of information about the current state of PHP. This includes information about PHP compilation options and extensions, the PHP version, server information and environment (if compiled as a module), the PHP environment, OS version information, paths, master and local values of configuration options, HTTP headers, and the GNU Public License.
See also phpversion().
string phpversion
(void);Returns a string containing the version of the currently running PHP parser.
Example 1. phpversion() example // prints e.g. 'Current PHP version: 3.0rel-dev' echo "Current PHP version: ".phpversion(); |
See also phpinfo().
bool extension_loaded
(string name);Returns true if the extension identified by name is loaded. You can see the names of various extensions by using phpinfo().
See also phpinfo().
Note: This function was added in 3.0.10.
void putenv
(string setting);Adds setting to the environment.
Example 1. Setting an Environment Variable putenv("UNIQID=$uniqid"); |
long set_magic_quotes_runtime
(int new_setting);Set the current active configuration setting of magic_quotes_runtime. (0 for off, 1 for on)
See also get_magic_quotes_gpc(), get_magic_quotes_runtime().
void set_time_limit
(int seconds);Set the number of seconds a script is allowed to run. If this is reached, the script returns a fatal error. The default limit is 30 seconds or, if it exists, the max_execution_time value defined in the configuration file. If seconds is set to zero, no time limit is imposed.
When called, set_time_limit() restarts the timeout counter from zero. In other words, if the timeout is the default 30 seconds, and 25 seconds into script execution a call such as set_time_limit(20) is made, the script will run for a total of 45 seconds before timing out.
The Informix driver for Online (ODS) 7.x, SE 7.x and Universal Server (IUS) 9.x is implemented in "functions/ifx.ec" and "functions/php3_ifx.h". ODS 7.x support is fairly complete, with full support for BYTE and TEXT columns. IUS 9.x support is partly finished: the new data types are there, but SLOB and CLOB support is still under construction.
Configuration notes:
Before you run the "configure" script, make sure that the "INFORMIXDIR" variable has been set.
The configure script will autodetect the libraries and include directories, if you run "configure --with_informix=yes". You can overide this detection by specifying "IFX_LIBDIR", "IFX_LIBS" and "IFX_INCDIR" in the environment. The configure script will also try to detect your Informix server version. It will set the "HAVE_IFX_IUS" conditional compilation variable if your Informix version >= 9.00.
Some notes on the use of BLOBs (TEXT and BYTE columns):
BLOBs are normally addressed by integer BLOB identifiers. Select queries return a "blob id" for every BYTE and TEXT column. You can get at the contents with "string_var = ifx_get_blob($blob_id);" if you choose to get the BLOBs in memory (with : "ifx_blobinfile(0);"). If you prefer to receive the content of BLOB columns in a file, use "ifx_blobinfile(1);", and "ifx_get_blob($blob_id);" will get you the filename. Use normal file I/O to get at the blob contents.
For insert/update queries you must create these "blob id's" yourself with "ifx_create_blob(..);". You then plug the blob id's into an array, and replace the blob columns with a question mark (?) in the query string. For updates/inserts, you are responsible for setting the blob contents with ifx_update_blob(...).
The behaviour of BLOB columns can be altered by configuration variables that also can be set at runtime :
configuration variable : ifx.textasvarchar
configuration variable : ifx.byteasvarchar
runtime functions :
ifx_textasvarchar(0) : use blob id's for select queries with TEXT columns
ifx_byteasvarchar(0) : use blob id's for select queries with BYTE columns
ifx_textasvarchar(1) : return TEXT columns as if they were VARCHAR columns, without the use of blob id's for select queries.
ifx_byteasvarchar(1) : return BYTE columns as if they were VARCHAR columns, without the use of blob id's for select queries.
configuration variable : ifx.blobinfile
runtime function :
ifx_blobinfile_mode(0) : return BYTE columns in memory, the blob id lets you get at the contents.
ifx_blobinfile_mode(1) : return BYTE columns in a file, the blob id lets you get at the file name.
If you set ifx_text/byteasvarchar to 1, you can use TEXT and BYTE columns in select queries just like normal (but rather long) VARCHAR fields. Since all strings are "counted" in PHP, this remains "binary safe". It is up to you to handle this correctly. The returned data can contain anything, you are responsible for the contents.
If you set ifx_blobinfile to 1, use the file name returned by ifx_get_blob(..) to get at the blob contents. Note that in this case YOU ARE RESPONSIBLE FOR DELETING THE TEMPORARY FILES CREATED BY INFORMIX when fetching the row. Every new row fetched will create new temporary files for every BYTE column.
The location of the temporary files can be influenced by the environment variable "blobdir", default is "." (the current directory). Something like : putenv(blobdir=tmpblob"); will ease the cleaning up of temp files accidentally left behind (their names all start with "blb").
Automatically trimming "char" (SQLCHAR and SQLNCHAR) data:
This can be set with the configuration variable
ifx.charasvarchar : if set to 1 trailing spaces will be automatically trimmed.
NULL values:
The configuration variable ifx.nullformat (and the runtime function ifx_nullformat()) when set to true will return NULL columns as the string "NULL", when set to false they return the empty string. This allows you to discriminate between NULL columns and empty columns.
int ifx_connect
(string [database]
, string [userid]
, string [password]
);Returns an connection identifier on success, or FALSE on error.
ifx_connect() establishes a connection to an Informix server. All of the arguments are optional, and if they're missing, defaults are taken from values supplied in configuration file (ifx.default_host for the host (Informix libraries will use INFORMIXSERVER environment value if not defined), ifx.default_user for user, ifx.default_password for the password (none if not defined).
In case a second call is made to ifx_connect() with the same arguments, no new link will be established, but instead, the link identifier of the already opened link will be returned.
The link to the server will be closed as soon as the execution of the script ends, unless it's closed earlier by explicitly calling ifx_close().
See also ifx_pconnect(), and ifx_close().
Example 1. Connect to a Informix database $conn_id = ifx_pconnect (mydb@ol_srv1, "imyself", "mypassword"); |
int ifx_pconnect
(string [database]
, string [userid]
, string [password]
);Returns: A positive Informix persistent link identifier on success, or false on error
ifx_pconnect() acts very much like ifx_connect() with two major differences.
This function behaves exactly like ifx_connect() when PHP is not running as an Apache module. First, when connecting, the function would first try to find a (persistent) link that's already open with the same host, username and password. If one is found, an identifier for it will be returned instead of opening a new connection.
Second, the connection to the SQL server will not be closed when the execution of the script ends. Instead, the link will remain open for future use (ifx_close() will not close links established by ifx_pconnect()).
This type of links is therefore called 'persistent'.
See also: ifx_connect().
int ifx_close
(int [link_identifier]
);Returns: always true.
ifx_close() closes the link to an Informix database that's associated with the specified link identifier. If the link identifier isn't specified, the last opened link is assumed.
Note that this isn't usually necessary, as non-persistent open links are automatically closed at the end of the script's execution.
ifx_close() will not close persistent links generated by ifx_pconnect().
See also: ifx_connect(), and ifx_pconnect().
Example 1. Closing a Informix connection $conn_id = ifx_connect (mydb@ol_srv, "itsme", "mypassword"); ... some queries and stuff ... ifx_close($conn_id); |
int ifx_query
(string query, int [link_identifier]
, int [cursor_type]
, mixed [blobidarray]
);Returns: A positive Informix result identifier on success, or false on error.
An integer "result_id" used by other functions to retrieve the query results. Sets "affected_rows" for retrieval by the ifx_affected_rows() function.
ifx_query() sends a query to the currently active database on the server that's associated with the specified link identifier. If the link identifier isn't specified, the last opened link is assumed. If no link is open, the function tries to establish a link as if ifx_connect() was called, and use it.
Executes query on connection conn_id. For "select-type" queries a cursor is declared and opened. The optional cursor_type parameter allows you to make this a "scroll" and/or "hold" cursor. It's a mask and can be either IFX_SCROLL, IFX_HOLD, or both or'ed together. Non-select queries are "execute immediate".
For either query type the number of (estimated or real) affected rows is saved for retrieval by ifx_affected_rows().
If you have BLOB (BYTE or TEXT) columns in an update query, you can add a blobidarray parameter containing the corresponding "blob ids", and you should replace those columns with a "?" in the query text.
If the contents of the TEXT (or BYTE) column allow it, you can also use "ifx_textasvarchar(1)" and "ifx_byteasvarchar(1)". This allows you to treat TEXT (or BYTE) columns just as if they were ordinary (but long) VARCHAR columns for select queries, and you don't need to bother with blob id's.
With ifx_textasvarchar(0) or ifx_byteasvarchar(0) (the default situation), select queries will return BLOB columns as blob id's (integer value). You can get the value of the blob as a string or file with the blob functions (see below).
See also: ifx_connect().
Example 1. Show all rows of the "orders" table as a html table ifx_textasvarchar(1); // use "text mode" for blobs $res_id = ifx_query("select * from orders", $conn_id); if (! $res_id) { printf("Can't select orders : %s\n<br>%s<br>\n", ifx_error()); ifx_errormsg(); die; } ifx_htmltbl_result($res_id, "border=\"1\""); ifx_free_result($res_id); |
Example 2. Insert some values into the "catalog" table // create blob id's for a byte and text column $textid = ifx_create_blob(0, 0, "Text column in memory"); $byteid = ifx_create_blob(1, 0, "Byte column in memory"); // store blob id's in a blobid array $blobidarray[] = $textid; $blobidarray[] = $byteid; // launch query $query = "insert into catalog (stock_num, manu_code, " . "cat_descr,cat_picture) values(1,'HRO',?,?)"; $res_id = ifx_query($query, $conn_id, $blobidarray); if (! $res_id) { ... error ... } // free result id ifx_free_result($res_id); |
int ifx_prepare
(string query, int conn_id, int [cursor_def], mixed blobidarray);Returns a integer result_id for use by ifx_do(). Sets affected_rows for retrieval by the ifx_affected_rows() function.
Prepares query on connection conn_id. For "select-type" queries a cursor is declared and opened. The optional cursor_type parameter allows you to make this a "scroll" and/or "hold" cursor. It's a mask and can be either IFX_SCROLL, IFX_HOLD, or both or'ed together.
For either query type the estimated number of affected rows is saved for retrieval by ifx_affected_rows().
If you have BLOB (BYTE or TEXT) columns in the query, you can add a blobidarray parameter containing the corresponding "blob ids", and you should replace those columns with a "?" in the query text.
If the contents of the TEXT (or BYTE) column allow it, you can also use "ifx_textasvarchar(1)" and "ifx_byteasvarchar(1)". This allows you to treat TEXT (or BYTE) columns just as if they were ordinary (but long) VARCHAR columns for select queries, and you don't need to bother with blob id's.
With ifx_textasvarchar(0) or ifx_byteasvarchar(0) (the default situation), select queries will return BLOB columns as blob id's (integer value). You can get the value of the blob as a string or file with the blob functions (see below).
See also: ifx_do().
int ifx_do
(int result_id);Returns TRUE on success, FALSE on error.
Executes a previously prepared query or opens a cursor for it.
Does NOT free result_id on error.
Also sets the real number of ifx_affected_rows() for non-select statements for retrieval by ifx_affected_rows()
See also: ifx_prepare(). There is a example.
string ifx_error
(void);The Informix error codes (SQLSTATE & SQLCODE) formatted as follows :
x [SQLSTATE = aa bbb SQLCODE=cccc]
where x = space : no error
E : error
N : no more data
W : warning
? : undefined
If the "x" character is anything other than space, SQLSTATE and SQLCODE describe the error in more detail.
See the Informix manual for the description of SQLSTATE and SQLCODE
Returns in a string one character describing the general results of a statement and both SQLSTATE and SQLCODE associated with the most recent SQL statement executed. The format of the string is "(char) [SQLSTATE=(two digits) (three digits) SQLCODE=(one digit)]". The first character can be ' ' (space) (success), 'W' (the statement caused some warning), 'E' (an error happened when executing the statement) or 'N' (the statement didn't return any data).
See also: ifx_errormsg()
string ifx_errormsg
(int [errorcode]);Returns the Informix error message associated with the most recent Informix error, or, when the optional "errorcode" param is present, the error message corresponding to "errorcode".
See also: ifx_error()
printf("%s\n<br>", ifx_errormsg(-201));
int ifx_affected_rows
(int result_id);result_id is a valid result id returned by ifx_query() or ifx_prepare().
Returns the number of rows affected by a query associated with result_id.
For inserts, updates and deletes the number is the real number (sqlerrd[2]) of affected rows. For selects it is an estimate (sqlerrd[0]). Don't rely on it.
Useful after ifx_prepare() to limit queries to reasonable result sets.
See also: ifx_num_rows()
Example 1. Informix affected rows $rid = ifx_prepare ("select * from emp where name like " . $name, $connid); if (! $rid) { ... error ... } $rowcount = ifx_affected_rows ($rid); if ($rowcount > 1000) { printf ("Too many rows in result set (%d)\n<br>", $rowcount); die ("Please restrict your query<br>\n"); } |
array ifx_getsqlca
(int result_id);result_id is a valid result id returned by ifx_query() or ifx_prepare().
Returns a pseudo-row (assiociative arry) with sqlca.sqlerrd[0] to sqlca.sqlerrd[5] after the query associated with result_id.
For inserts, updates and deletes the values returned are those as set by the server after executing the query. This gives access to the number of affected rows and the serial insert value. For selects the values are those saved after the prepare statement. This gives access to the estimated number of affected rows. The use of this function saves the overhead of executing a "select dbinfo('sqlca.sqlerrdx')" query, as it retrieves the values that were saved by the ifx driver at the appropriate moment.
Example 1. Retrieve Informix sqlca.sqlerrd[x] values /* assume the first column of 'sometable' is a serial */ $qid = ifx_query("insert into sometable values(0, '2nd column', 'another column' ", $connid); if (! $qid) { ... error ... } $sqlca = ifx_getsqlca ($qid); $serial_value = $sqlca["sqlerrd1"]; echo "The serial value of the inserted row is : " . $serial_value<br>\n"; |
array ifx_fetch_row
(int result_id, mixed [position]
);Returns an associative array that corresponds to the fetched row, or false if there are no more rows.
Blob columns are returned as integer blob id values for use in ifx_get_blob() unless you have used ifx_textasvarchar(1) or ifx_byteasvarchar(1), in which case blobs are returned as string values. Returns FALSE on error
result_id is a valid resultid returned by ifx_query() or ifx_prepare() (select type queries only!).
[position] is an optional parameter for a "fetch" operation on "scroll" cursors: "NEXT", "PREVIOUS", "CURRENT", "FIRST", "LAST" or a number. If you specify a number, an "absolute" row fetch is executed. This parameter is optional, and only valid for scrollcursors.
ifx_fetch_row() fetches one row of data from the result associated with the specified result identifier. The row is returned as an array. Each result column is stored in an array offset, starting at offset 0.
Subsequent call to ifx_fetch_row() would return the next row in the result set, or false if there are no more rows.
Example 1. Informix fetch rows $rid = ifx_prepare ("select * from emp where name like " . $name, $connid, IFX_SCROLL); if (! $rid) { ... error ... } $rowcount = ifx_affected_rows($rid); if ($rowcount > 1000) { printf ("Too many rows in result set (%d)\n<br>", $rowcount); die ("Please restrict your query<br>\n"); } if (! ifx_do ($rid)) { ... error ... } $row = ifx_fetch_row ($rid, "NEXT"); while (is_array($row)) { for(reset($row); $fieldname=key($row); next($row)) { $fieldvalue = $row[$fieldname]; printf ("%s = %s,", $fieldname, $fieldvalue); } printf("\n<br>"); $row = ifx_fetch_row ($rid, "NEXT"); } ifx_free_result ($rid); |
int ifx_htmltbl_result
(int result_id, string [html_table_options]);Returns the number of rows fetched or FALSE on error.
Formats all rows of the result_id query into a html table. The optional second argument is a string of <table> tag options
Example 1. Informix results as HTML table $rid = ifx_prepare ("select * from emp where name like " . $name, $connid, IFX_SCROLL); if (! $rid) { ... error ... } $rowcount = ifx_affected_rows ($rid); if ($rowcount > 1000) { printf ("Too many rows in result set (%d)\n<br>", $rowcount); die ("Please restrict your query<br>\n"); } if (! ifx_do($rid) { ... error ... } ifx_htmltbl_result ($rid, "border=\"2\""); ifx_free_result($rid); |
array ifx_fieldtypes
(int result_id);Returns an associative array with fieldnames as key and the SQL fieldtypes as data for query with result_id. Returns FALSE on error.
Example 1. Fielnames and SQL fieldtypes $types = ifx_fieldtypes ($resultid); if (! isset ($types)) { ... error ... } for ($i = 0; $i < count($types); $i++) { $fname = key($types); printf("%s :\t type = %s\n", $fname, $types[$fname]); next($types); } |
array ifx_fieldproperties
(int result_id);Returns an associative array with fieldnames as key and the SQL fieldproperties as data for a query with result_id. Returns FALSE on error.
Returns the Informix SQL fieldproperies of every field in the query as an associative array. Properties are encoded as: "SQLTYPE;length;precision;scale;ISNULLABLE" where SQLTYPE = the Informix type like "SQLVCHAR" etc. and ISNULLABLE = "Y" or "N".
Example 1. Informix SQL fieldproperties $properties = ifx_fieldtypes ($resultid); if (! isset($properties)) { ... error ... } for ($i = 0; $i < count($properties); $i++) { $fname = key ($properties); printf ("%s:\t type = %s\n", $fname, $properties[$fname]); next ($properties); } |
int ifx_num_fields
(int result_id);Returns the number of columns in query for result_id or FALSE on error
After preparing or executing a query, this call gives you the number of columns in the query.
int ifx_num_rows
(int result_id);Gives the number of rows fetched so far for a query with result_id after a ifx_query() or ifx_do() query.
int ifx_free_result
(int result_id);Releases resources for the query associated with result_id. Returns FALSE on error.
int ifx_create_char
(string param);Creates an char object. param should be the char content.
int ifx_free_char
(int bid);Deletes the charobject for the given char object-id bid. Returns FALSE on error otherwise TRUE.
int ifx_update_char
(int bid, string content);Updates the content of the char object for the given char object bid. content is a string with new data. Returns FALSE on error otherwise TRUE.
int ifx_get_char
(int bid);Returns the content of the char object for the given char object-id bid.
int ifx_create_blob
(int type, int mode, string param);Creates an blob object.
type: 1 = TEXT, 0 = BYTE
mode: 0 = blob-object holds the content in memory, 1 = blob-object holds the content in file.
param: if mode = 0: pointer to the content, if mode = 1: pointer to the filestring.
Return FALSE on error, otherwise the new blob object-id.
int ifx_copy_blob
(int bid);Duplicates the given blob object. bid is the ID of the blob object.
Returns FALSE on error otherwise the new blob object-id.
int ifx_free_blob
(int bid);Deletes the blobobject for the given blob object-id bid. Returns FALSE on error otherwise TRUE.
int ifx_get_blob
(int bid);Returns the content of the blob object for the given blob object-id bid.
ifx_update_blob
(int bid, string content);Updates the content of the blob object for the given blob object bid. content is a string with new data. Returns FALSE on error otherwise TRUE.
void ifx_blobinfile_mode
(int mode);Set the default blob mode for all select queries. Mode "0" means save Byte-Blobs in memory, and mode "1" means save Byte-Blobs in a file.
void ifx_textasvarchar
(int mode);Sets the default text mode for all select-queries. Mode "0" will return a blob id, and mode "1" will return a varchar with text content.
void ifx_byteasvarchar
(int mode);Sets the default byte mode for all select-queries. Mode "0" will return a blob id, and mode "1" will return a varchar with text content.
void ifx_nullformat
(int mode);Sets the default return value of a NULL-value on a fetch row. Mode "0" returns "", and mode "1" returns "NULL".
int ifxus_create_slob
(int mode);Creates an slob object and opens it. Modes: 1 = LO_RDONLY, 2 = LO_WRONLY, 4 = LO_APPEND, 8 = LO_RDWR, 16 = LO_BUFFER, 32 = LO_NOBUFFER -> or-mask. You can also use constants named IFX_LO_RDONLY, IFX_LO_WRONLY etc. Return FALSE on error otherwise the new slob object-id.
int ifxus_free_slob
(int bid);Deletes the slob object. bid is the Id of the slob object. Returns FALSE on error otherwise TRUE.
int ifxus_close_slob
(int bid);Deletes the slob object on the given slob object-id bid. Return FALSE on error otherwise TRUE.
int ifxus_open_slob
(long bid, int mode);Opens an slob object. bid should be an existing slob id. Modes: 1 = LO_RDONLY, 2 = LO_WRONLY, 4 = LO_APPEND, 8 = LO_RDWR, 16 = LO_BUFFER, 32 = LO_NOBUFFER -> or-mask. Returns FALSE on error otherwise the new slob object-id.
int ifxus_tell_slob
(long bid);Returns the current file or seek position of an open slob object bid should be an existing slob id. Return FALSE on error otherwise the seek position.
int ifxus_seek_blob
(long bid, int mode, long offset);Sets the current file or seek position of an open slob object. bid should be an existing slob id. Modes: 0 = LO_SEEK_SET, 1 = LO_SEEK_CUR, 2 = LO_SEEK_END and offset is an byte offset. Return FALSE on error otherwise the seek position.
int ifxus_read_slob
(long bid, long nbytes);Reads nbytes of the slob object. bid is a existing slob id and nbytes is the number of bytes zu read. Return FALSE on error otherwise the string.
LDAP is the Lightweight Directory Access Protocol, and is a protocol used to access "Directory Servers". The Directory is a special kind of database that holds information in a tree structure.
The concept is similar to your hard disk directory structure, except that in this context, the root directory is "The world" and the first level subdirectories are "countries". Lower levels of the directory structure contain entries for companies, organisations or places, while yet lower still we find directory entries for people, and perhaps equipment or documents.
To refer to a file in a subdirectory on your hard disk, you might use something like
/usr/local/myapp/docs
The forwards slash marks each division in the reference, and the sequence is read from left to right.
The equivalent to the fully qualified file reference in LDAP is the "distinguished name", referred to simply as "dn". An example dn might be.
cn=John Smith,ou=Accounts,o=My Company,c=US
The comma marks each division in the reference, and the sequence is read from right to left. You would read this dn as ..
country = US
organization = My Company
organizationalUnit = Accounts
commonName = John Smith
In the same way as there are no hard rules about how you organise the directory structure of a hard disk, a directory server manager can set up any structure that is meaningful for the purpose. However, there are some conventions that are used. The message is that you can not write code to access a directory server unless you know something about its structure, any more than you can use a database without some knowledge of what is available.
Retrieve information for all entries where the surname starts with "S" from a directory server, displaying an extract with name and email address.
Example 1. LDAP search example <?php // basic sequence with LDAP is connect, bind, search, interpret search // result, close connection echo "<h3>LDAP query test</h3>"; echo "Connecting ..."; $ds=ldap_connect("localhost"); // must be a valid LDAP server! echo "connect result is ".$ds."<p>"; if ($ds) { echo "Binding ..."; $r=ldap_bind($ds); // this is an "anonymous" bind, typically // read-only access echo "Bind result is echo "Bind result is ".$r."<p>"; echo "Searching for (sn=S*) ..."; // Search surname entry $sr=ldap_search($ds,"o=My Company, c=US", "sn=S*"); echo "Search result is ".$sr."<p>"; echo "Number of entires returned is ".ldap_count_entries($ds,$sr)."<p>"; echo "Getting entries ...<p>"; $info = ldap_get_entries($ds, $sr); echo "Data for ".$info["count"]." items returned:<p>"; for ($i=0; $i<$info["count"]; $i++) { echo "dn is: ". $info[$i]["dn"] ."<br>"; echo "first cn entry is: ". $info[$i]["cn"][0] ."<br>"; echo "first email entry is: ". $info[$i]["mail"][0] ."<p>"; } echo "Closing connection"; ldap_close($ds); } else { echo "<h4>Unable to connect to LDAP server</h4>"; } ?> |
You will need to get and compile LDAP client libraries from either the University of Michigan ldap-3.3 package or the Netscape Directory SDK. You will also need to recompile PHP with LDAP support enabled before PHP's LDAP calls will work.
Before you can use the LDAP calls you will need to know ..
The name or address of the directory server you will use
The "base dn" of the server (the part of the world directory that is held on this server, which could be "o=My Company,c=US")
Whether you need a password to access the server (many servers will provide read access for an "anonymous bind" but require a password for anything else)
The typical sequence of LDAP calls you will make in an application will follow this pattern:
ldap_connect() // establish connection to server
|
ldap_bind() // anonymous or authenticated "login"
|
do something like search or update the directory
and display the results
|
ldap_close() // "logout"
Lots of information about LDAP can be found at
The Netscape SDK contains a helpful Programmer's Guide in .html format.
int ldap_add
(int link_identifier, string dn, array entry);returns true on success and false on error.
The ldap_add() function is used to add entries in the LDAP directory. The DN of the entry to be added is specified by dn. Array entry specifies the information about the entry. The values in the entries are indexed by individual attributes. In case of multiple values for an attribute, they are indexed using integers starting with 0.
entry["attribute1"] = value
entry["attribute2"][0] = value1
entry["attribute2"][1] = value2
Example 1. Complete example with authenticated bind <?php $ds=ldap_connect("localhost"); // assuming the LDAP server is on this host if ($ds) { // bind with appropriate dn to give update access $r=ldap_bind($ds,"cn=root, o=My Company, c=US", "secret"); // prepare data $info["cn"]="John Jones"; $info["sn"]="Jones"; $info["mail"]="jonj@here.and.now"; $info["objectclass"]="person"; // add data to directory $r=ldap_add($ds, "cn=John Jones, o=My Company, c=US", $info); ldap_close($ds); } else { echo "Unable to connect to LDAP server"; } ?> |
int ldap_mod_add
(int link_identifier, string dn, array entry);returns true on success and false on error.
This function adds attribute(s) to the specified dn. It performs the modification at the attribute level as opposed to the object level. Object-level additions are done by the ldap_add() function.
int ldap_mod_del
(int link_identifier, string dn, array entry);returns true on success and false on error.
This function removes attribute(s) from the specified dn. It performs the modification at the attribute level as opposed to the object level. Object-level deletions are done by the ldap_del() function.
int ldap_mod_replace
(int link_identifier, string dn, array entry);returns true on success and false on error.
This function replaces attribute(s) from the specified dn. It performs the modification at the attribute level as opposed to the object level. Object-level modifications are done by the ldap_modify() function.
int ldap_bind
(int link_identifier, string [bind_rdn], string [bind_password]);Binds to the LDAP directory with specified RDN and password. Returns true on success and false on error.
ldap_bind() does a bind operation on the directory. bind_rdn and bind_password are optional. If not specified, anonymous bind is attempted.
int ldap_close
(int link_identifier);Returns true on success, false on error.
ldap_close() closes the link to the LDAP server that's associated with the specified link_identifier.
This call is internally identical to ldap_unbind(). The LDAP API uses the call ldap_unbind(), so perhaps you should use this in preference to ldap_close().
int ldap_connect
(string [hostname], int [port]);Returns a positive LDAP link identifier on success, or false on error.
ldap_connect() establishes a connection to a LDAP server on a specified hostname and port. Both the arguments are optional. If no arguments are specified then the link identifier of the already opened link will be returned. If only hostname is specified, then the port defaults to 389.
int ldap_count_entries
(int link_identifier, int result_identifier);Returns number of entries in the result or false on error.
ldap_count_entries() returns the number of entries stored in the result of previous search operations. result_identifier identifies the internal ldap result.
int ldap_delete
(int link_identifier, string dn);Returns true on success and false on error.
ldap_delete() function delete a particular entry in LDAP directory specified by dn.
string ldap_dn2ufn
(string dn);ldap_dn2ufn() function is used to turn a DN into a more user-friendly form, stripping off type names.
array ldap_explode_dn
(string dn, int with_attrib);ldap_explode_dn() function is used to split the a DN returned by ldap_get_dn() and breaks it up into its component parts. Each part is known as Relative Distinguished Name, or RDN. ldap_explode_dn() returns an array of all those components. with_attrib is used to request if the RDNs are returned with only values or their attributes as well. To get RDNs with the attributes (i.e. in attribute=value format) set with_attrib to 0 and to get only values set it to 1.
string ldap_first_attribute
(int link_identifier, int result_entry_identifier, int ber_identifier);Returns the first attribute in the entry on success and false on error.
Similar to reading entries, attributes are also read one by one from a particular entry. ldap_first_attribute() returns the first attribute in the entry pointed by the entry identifier. Remaining attributes are retrieved by calling ldap_next_attribute() successively. ber_identifier is the identifier to internal memory location pointer. It is passed by reference. The same ber_identifier is passed to the ldap_next_attribute() function, which modifies that pointer.
see also ldap_get_attributes()
int ldap_first_entry
(int link_identifier, int result_identifier);Returns the result entry identifier for the first entry on success and false on error.
Entries in the LDAP result are read sequentially using the ldap_first_entry() and ldap_next_entry() functions. ldap_first_entry() returns the entry identifier for first entry in the result. This entry identifier is then supplied to lap_next_entry() routine to get successive entries from the result.
see also ldap_get_entries().
int ldap_free_result
(int result_identifier);Returns true on success and false on error.
ldap_free_result() frees up the memory allocated internally to store the result and pointed by the result_identifier. All result memory will be automatically freed when the script terminates.
Typically all the memory allocated for the ldap result gets freed at the end of the script. In case the script is making successive searches which return large result sets, ldap_free_result() could be called to keep the runtime memory usage by the script low.
array ldap_get_attributes
(int link_identifier, int
result_entry_identifier);Returns a complete entry information in a multi-dimensional array on success and false on error.
ldap_get_attributes() function is used to simplify reading the attributes and values from an entry in the search result. The return value is a multi-dimensional array of attributes and values.
Having located a specific entry in the directory, you can find out what information is held for that entry by using this call. You would use this call for an application which "browses" directory entries and/or where you do not know the structure of the directory entries. In many applications you will be searching for a specific attribute such as an email address or a surname, and won't care what other data is held.
return_value["count"] = number of attributes in the entry
return_value[0] = first attribute
return_value[n] = nth attribute
return_value["attribute"]["count"] = number of values for attribute
return_value["attribute"][0] = first value of the attribute
return_value["attribute"][i] = ith value of the attribute
Example 1. Show the list of attributes held for a particular directory entry // $ds is the link identifier for the directory // $sr is a valid search result from a prior call to // one of the ldap directory search calls $entry = ldap_first_entry($ds, $sr); $attrs = ldap_get_attributes($ds, $entry); echo $attrs["count"]." attributes held for this entry:<p>"; for ($i=0; $i<$attrs["count"]; $i++) echo $attrs[$i]."<br>"; |
see also ldap_first_attribute() and ldap_next_attribute()
string ldap_get_dn
(int link_identifier, int result_entry_identifier);Returns the DN of the result entry and false on error.
ldap_get_dn() function is used to find out the DN of an entry in the result.
array ldap_get_entries
(int link_identifier, int result_identifier);Returns a complete result information in a multi-dimenasional array on success and false on error.
ldap_get_entries() function is used to simplify reading multiple entries from the result and then reading the attributes and multiple values. The entire information is returned by one function call in a multi-dimensional array. The structure of the array is as follows.
The attribute index is converted to lowercase. (Attributes are case-insensitive for directory servers, but not when used as array indices)
return_value["count"] = number of entries in the result
return_value[0] : refers to the details of first entry
return_value[i]["dn"] = DN of the ith entry in the result
return_value[i]["count"] = number of attributes in ith entry
return_value[i][j] = jth attribute in the ith entry in the result
return_value[i]["attribute"]["count"] = number of values for
attribute in ith entry
return_value[i]["attribute"][j] = jth value of attribute in ith entry
see also ldap_first_entry() and ldap_next_entry()
array ldap_get_values
(int link_identifier, int result_entry_identifier, string attribute);Returns an array of values for the attribute on success and false on error.
ldap_get_values() function is used to read all the values of the attribute in the entry in the result. entry is specified by the result_entry_identifier. The number of values can be found by indexing "count" in the resultant array. Individual values are accessed by integer index in the array. The first index is 0.
This call needs a result_entry_identifier, so needs to be preceded by one of the ldap search calls and one of the calls to get an individual entry.
You application will either be hard coded to look for certain attributes (such as "surname" or "mail") or you will have to use the ldap_get_attributes() call to work out what attributes exist for a given entry.
LDAP allows more than one entry for an attribute, so it can, for example, store a number of email addresses for one person's directory entry all labeled with the attribute "mail"
return_value["count"] = number of values for attribute
return_value[0] = first value of attribute
return_value[i] = ith value of attribute
Example 1. List all values of the "mail" attribute for a directory entry // $ds is a valid link identifier for a directory server // $sr is a valid search result from a prior call to // one of the ldap directory search calls // $entry is a valid entry identifier from a prior call to // one of the calls that returns a directory entry $values = ldap_get_values($ds, $entry,"mail"); echo $values["count"]." email addresses for this entry.<p>"; for ($i=0; $i < $values["count"]; $i++) echo $values[$i]."<br>"; |
int ldap_list
(int link_identifier, string base_dn, string filter, array
[attributes]);Returns a search result identifier or false on error.
ldap_list() performs the search for a specified filter on the directory with the scope LDAP_SCOPE_ONELEVEL.
LDAP_SCOPE_ONELEVEL means that the search should only return information that is at the level immediately below the base dn given in the call. (Equivalent to typing "ls" and getting a list of files and folders in the current working directory.)
This call takes an optional fourth parameter which is an array of the attributes required. See ldap_search() notes.
Example 1. Produce a list of all organizational units of an organization // $ds is a valid link identifier for a directory server $basedn = "o=My Company, c=US"; $justthese = array("ou"); $sr=ldap_list($ds, $basedn, "ou=*", $justthese); $info = ldap_get_entries($ds, $sr); for ($i=0; $i<$info["count"]; $i++) echo $info[$i]["ou"][0] ; |
int ldap_modify
(int link_identifier, string dn, array entry);Returns true on success and false on error.
ldap_modify() function is used to modify the existing entries in the LDAP directory. The structure of the entry is same as in ldap_add().
string ldap_next_attribute
(int link_identifier, int result_entry_identifier, int ber_identifier);Returns the next attribute in an entry on success and false on error.
ldap_next_attribute() is called to retrieve the attributes in an entry. The internal state of the pointer is maintained by the ber_identifier. It is passed by reference to the function. The first call to ldap_next_attribute() is made with the result_entry_identifier returned from ldap_first_attribute().
see also ldap_get_attributes()
int ldap_next_entry
(int link_identifier, int result_entry_identifier);Returns entry identifier for the next entry in the result whose entries are being read starting with ldap_first_entry(). If there are no more entries in the result then it returns false.
ldap_next_entry() function is used to retrieve the entries stored in the result. Successive calls to the ldap_next_entry() return entries one by one till there are no more entries. The first call to ldap_next_entry() is made after the call to ldap_first_entry() with the result_identifier as returned from the ldap_first_entry().
see also ldap_get_entries()
int ldap_read
(int link_identifier, string base_dn, string filter, array
[attributes]);Returns a search result identifier or false on error.
ldap_read() performs the search for a specified filter on the directory with the scope LDAP_SCOPE_BASE. So it is equivalent to reading an entry from the directory.
An empty filter is not allowed. If you want to retrieve absolutely all information for this entry, use a filter of "objectClass=*". If you know which entry types are used on the directory server, you might use an appropriate filter such as "objectClass=inetOrgPerson".
This call takes an optional fourth parameter which is an array of the attributes required. See ldap_search() notes.
int ldap_search
(int link_identifier, string base_dn, string filter, array
[attributes]);Returns a search result identifier or false on error.
ldap_search() performs the search for a specified filter on the directory with the scope of LDAP_SCOPE_SUBTREE. This is equivalent to searching the entire directory. base_dn specifies the base DN for the directory.
There is a optional fourth parameter, that can be added to restrict the attributes and values returned by the server to just those required. This is much more efficient than the default action (which is to return all attributes and their associated values). The use of the fourth parameter should therefore be considered good practice.
The fourth parameter is a standard PHP string array of the required attributes, eg array("mail","sn","cn") Note that the "dn" is always returned irrespective of which attributes types are requested.
Note too that some directory server hosts will be configured to return no more than a preset number of entries. If this occurs, the server will indicate that it has only returned a partial results set.
The search filter can be simple or advanced, using boolean operators in the format described in the LDAP doumentation (see the Netscape Directory SDK for full information on filters).
The example below retrieves the organizational unit, surname, given name and email address for all people in "My Company" where the surname or given name contains the substring $person. This example uses a boolean filter to tell the server to look for information in more than one attribute.
Example 1. LDAP search // $ds is a valid link identifier for a directory server // $person is all or part of a person's name, eg "Jo" $dn = "o=My Company, c=US"; $filter="(|(sn=$person*)(givenname=$person*))"; $justthese = array( "ou", "sn", "givenname", "mail"); $sr=ldap_search($ds, $dn, $filter, $justthese); $info = ldap_get_entries($ds, $sr); print $info["count"]." entries returned<p>"; |
The mail() function allows you to send mail.
bool mail
(string to, string subject, string message, string [additional_headers]);Mail() automatically mails the message specified in message to the receiver specified in to. Multiple recipients can be specified by putting a comma between each address in to.
Example 1. Sending mail. mail("rasmus@lerdorf.on.ca", "My Subject", "Line 1\nLine 2\nLine 3"); |
If a fourth string argument is passed, this string is inserted at the end of the header. This is typically used to add extra headers. Multiple extra headers are separated with a newline.
Example 2. Sending mail with extra headers. mail("nobody@aol.com", "the subject", $message, "From: webmaster@$SERVER_NAME\nReply-To: webmaster@$SERVER_NAME\nX-Mailer: PHP/" . phpversion()); |
These math functions will only handle values within the range of the long and double types on your computer. If you need to handle bigger numbers, take a look at the arbitrary precision math functions.
The following values are defined as constants in PHP by the math extension:
Table 1. Math constants
Constant | Value | Description |
---|---|---|
M_PI | 3.14159265358979323846 | The value of ¶ (pi) |
mixed abs
(mixed number);Returns the absolute value of number. If the argument number is float, return type is also float, otherwise it is int.
float atan
(float arg);Returns the arc tangent of arg in radians.
See also acos() and atan().
float atan2
(float y, float x);This function calculates the arc tangent of the two variables x and y. It is similar to calculating the arc tangent of y / x, except that the signs of both arguments are used to determine the quadrant of the result.
The function returns the result in radians, which is between -PI and PI (inclusive).
strin base_convert
(string number, int frombase, int tobase);Returns a string containing number represented in base tobase. The base in which number is given is specified in frombase. Both frombase and tobase have to be between 2 and 36, inclusive. Digits in numbers with a base higher than 10 will be represented with the letters a-z, with a meaning 10, b meaning 11 and z meaning 36.
Example 1. base_convert() $binary = base_convert($hexadecimal, 16, 2); |
int bindec
(string binary_string);Returns the decimal equivalent of the binary number represented by the binary_string argument.
OctDec converts a binary number to a decimal number. The largest number that can be converted is 31 bits of 1's or 2147483647 in decimal.
See also the decbin() function.
int ceil
(float number);Returns the next highest integer value from number. Using ceil() on integers is absolutely a waste of time.
NOTE: PHP/FI 2's ceil() returned a float. Use: $new = (double)ceil($number); to get the old behaviour.
string decbin
(int number);Returns a string containing a binary representation of the given number argument. The largest number that can be converted is 2147483647 in decimal resulting to a string of 31 1's.
See also the bindec() function.
string dechex
(int number);Returns a string containing a hexadecimal representation of the given number argument. The largest number that can be converted is 2147483647 in decimal resulting to "7fffffff".
See also the hexdec() function.
string decoct
(int number);Returns a string containing an octal representation of the given number argument. The largest number that can be converted is 2147483647 in decimal resulting to "17777777777". See also octdec().
int floor
(float number);Returns the next lowest integer value from number. Using floor() on integers is absolutely a waste of time.
NOTE: PHP/FI 2's floor() returned a float. Use: $new = (double)floor($number); to get the old behaviour.
int getrandmax
(void );Returns the maximum value that can be returned by a call to rand().
See also rand(), srand() mt_rand(), mt_srand() and mt_getrandmax().
int hexdec
(string hex_string);Returns the decimal equivalent of the hexadecimal number represented by the hex_string argument. HexDec converts a hexadecimal string to a decimal number. The largest number that can be converted is 7fffffff or 2147483647 in decimal.
See also the dechex() function.
mixed max
(mixed arg1, mixed arg2, mixed argn);max() returns the numerically highest of the parameter values.
If the first parameter is an array, max() returns the highest value in that array. If the first parameter is an integer, string or double, you need at least two parameters and max() returns the biggest of these values. You can compare an unlimited number of values.
If one or more of the values is a double, all the values will be treated as doubles, and a double is returned. If none of the values is a double, all of them will be treated as integers, and an integer is returned.
mixed min
(mixed arg1, mixed arg2, mixed argn);min() returns the numerically lowest of the parameter values.
If the first parameter is an array, min() returns the lowest value in that array. If the first parameter is an integer, string or double, you need at least two parameters and min() returns the lowest of these values. You can compare an unlimited number of values.
If one or more of the values is a double, all the values will be treated as doubles, and a double is returned. If none of the values is a double, all of them will be treated as integers, and an integer is returned.
int mt_rand
([int min], [int max]);Many random number generators of older libcs have dubious or unknown characteristics and are slow. By default, PHP uses the libc random number generator with the rand() function. mt_rand() function is a drop-in replacement for this. It uses a random number generator with known characteristics, the Mersenne Twister, which will produce random numbers that should be suitable for cryptographic purposes and is four times faster than what the average libc provides. The Homepage of the Mersenne Twister can be found at http://www.math.keio.ac.jp/~matumoto/emt.html, and an optimized version of the MT source is available from http://www.scp.syr.edu/~marc/hawk/twister.html.
If called without the optional min,max arguments mt_rand() returns a pseudo-random value between 0 and RAND_MAX. If you want a random number between 5 and 15 (inclusive), for example, use mt_rand(5,15).
Remember to seed the random number generator before use with mt_srand().
See also mt_srand(), mt_getrandmax(), srand(), rand() and getrandmax().
void mt_srand
(int seed);Seeds the random number generator with seed.
// seed with microseconds since last "whole" second mt_srand((double)microtime()*1000000); $randval = mt_rand();
See also mt_rand(), mt_getrandmax(), srand(), rand() and getrandmax().
int mt_getrandmax
(void );Returns the maximum value that can be returned by a call to mt_rand().
See also mt_rand(), mt_srand() rand(), srand() and getrandmax().
string number_format
(float number, int decimals, string dec_point, string thousands_sep);number_format() returns a formatted version of number. This function accepts either one, two or four parameters (not three):
If only one parameter is given, number will be formatted without decimals, but with a comma (",") between every group of thousands.
If two parameters are given, number will be formatted with decimals decimals with a dot (".") in front, and a comma (",") between every group of thousands.
If all four parameters are given, number will be formatted with decimals decimals, dec_point instead of a dot (".") before the decimals and thousands_sep instead of a comma (",") between every group of thousands.
int octdec
(string octal_string);Returns the decimal equivalent of the octal number represented by the octal_string argument. OctDec converts an octal string to a decimal number. The largest number that can be converted is 17777777777 or 2147483647 in decimal.
See also decoct().
float pow
(float base, float exp);Returns base raised to the power of exp.
See also exp().
int rand
([int min], [int max]);If called without the optional min,max arguments rand() returns a pseudo-random value between 0 and RAND_MAX. If you want a random number between 5 and 15 (inclusive), for example, use rand(5,15).
Remember to seed the random number generator before use with srand().
See also srand(), getrandmax(), mt_rand(), mt_srand() and mt_getrandmax().
double round
(double val);Returns the rounded value of val.
$foo = round( 3.4 ); // $foo == 3.0 $foo = round( 3.5 ); // $foo == 4.0 $foo = round( 3.6 ); // $foo == 4.0
void srand
(int seed);Seeds the random number generator with seed.
// seed with microseconds since last "whole" second srand((double)microtime()*1000000); $randval = rand();
See also rand(), getrandmax(), mt_rand(), mt_srand() and mt_getrandmax().
These functions work using mcrypt.
This is an interface to the mcrypt library, which supports a wide variety of block algorithms such as DES, TripleDES, Blowfish (default), 3-WAY, SAFER-SK64, SAFER-SK128, TWOFISH, TEA, RC2 and GOST in CBC, OFB, CFB and ECB cipher modes. Additionally, it supports RC6 and IDEA which are considered "non-free".
To use it, download libmcrypt-x.x.tar.gz from here and follow the included installation instructions. You need to compile PHP with the --with-mcrypt parameter to enable this extension.
mcrypt can be used to encrypt and decrypt using the above mentioned ciphers. The four important mcrypt commands (mcrypt_cfb(), mcrypt_cbc(), mcrypt_ecb(), and mcrypt_ofb()) can operate in both modes which are named MCRYPT_ENCRYPT and MCRYPT_DECRYPT, respectively.
Example 1. Encrypt an input value with TripleDES in ECB mode <?php $key = "this is a very secret key"; $input = "Let us meet at 9 o'clock at the secret place."; $encrypted_data = mcrypt_ecb(MCRYPT_TripleDES, $key, $input, MCRYPT_ENCRYPT); ?> |
mcrypt can operate in four cipher modes (CBC, OFB, CFB, and ECB). We will outline the normal use for each of these modes. For a more complete reference and discussion see Applied Cryptography by Schneier (ISBN 0-471-11709-9).
ECB (electronic codebook) is suitable for random data, such as encrypting other keys. Since data there is short and random, the disadvantages of ECB have a favorable negative effect.
CBC (cipher block chaining) is especially suitable for encrypting files where the security is increased over ECB significantly.
CFB (cipher feedback) is the best mode for encrypting byte streams where single bytes must be encrypted.
OFB (output feedback) is comparable to CFB, but can be used in applications where error propagation cannot be tolerated.
PHP does not support encrypting/decrypting bit streams currently. As of now, PHP only supports handling of strings.
For a complete list of supported ciphers, see the defines at the end of mcrypt.h. The general rule is that you can access the cipher from PHP with MCRYPT_ciphername.
Here is a short list of ciphers which are currently supported by the mcrypt extension. If a cipher is not listed here, but is listed by mcrypt as supported, you can safely assume that this documentation is outdated.
MCRYPT_BLOWFISH
MCRYPT_DES
MCRYPT_TripleDES
MCRYPT_ThreeWAY
MCRYPT_GOST
MCRYPT_CRYPT
MCRYPT_DES_COMPAT
MCRYPT_SAFER64
MCRYPT_SAFER128
MCRYPT_CAST128
MCRYPT_TEAN
MCRYPT_RC2
MCRYPT_TWOFISH (for older mcrypt 2.x versions)
MCRYPT_TWOFISH128 (TWOFISHxxx are available in newer 2.x versions)
MCRYPT_TWOFISH192
MCRYPT_TWOFISH256
MCRYPT_RC6
MCRYPT_IDEA
You must (in CFB and OFB mode) or can (in CBC mode) supply an initialization vector (IV) to the respective cipher function. The IV must be unique and must be the same when decrypting/encrypting. With data which is stored encrypted, you can take the output of a function of the index under which the data is stored (e.g. the MD5 key of the filename). Alternatively, you can transmit the IV together with the encrypted data (see chapter 9.3 of Applied Cryptography by Schneier (ISBN 0-471-11709-9) for a discussion of this topic).
string mcrypt_get_cipher_name
(int cipher);mcrypt_get_cipher_name() is used to get the name of the specified cipher.
mcrypt_get_cipher_name() takes the cipher number as an argument and returns the name of the cipher or false, if the cipher does not exist.
Example 1. mcrypt_get_cipher_name example <?php $cipher = MCRYPT_TripleDES; print mcrypt_get_cipher_name($cipher); ?> |
The above example will produce:
TripleDES
int mcrypt_get_block_size
(int cipher);mcrypt_get_block_size() is used to get the size of a block of the specified cipher.
mcrypt_get_block_size() takes one argument, the cipher and returns the size in bytes.
See also: mcrypt_get_key_size()
int mcrypt_get_key_size
(int cipher);mcrypt_get_key_size() is used to get the size of a key of the specified cipher.
mcrypt_get_key_size() takes one argument, the cipher and returns the size in bytes.
See also: mcrypt_get_block_size()
string
mcrypt_create_iv
(int size, int source);mcrypt_create_iv() is used to create an IV.
mcrypt_create_iv() takes two arguments, size determines the size of the IV, source specifies the source of the IV.
The source can be MCRYPT_RAND (system random number generator), MCRYPT_DEV_RANDOM (read data from /dev/random) and MCRYPT_DEV_URANDOM (read data from /dev/urandom). If you use MCRYPT_RAND, make sure to call srand() before to initialize the random number generator.
Example 1. mcrypt_create_iv example <?php $cipher = MCRYPT_TripleDES; $block_size = mcrypt_get_block_size($cipher); $iv = mcrypt_create_iv($block_size, MCRYPT_DEV_RANDOM); ?> |
int mcrypt_cbc
(int cipher, string key, string data, int mode, string [iv]);mcrypt_cbc() encrypts or decrypts (depending on mode) the data with cipher and key in CBC cipher mode and returns the resulting string.
cipher is one of the MCRYPT_ciphername constants.
key is the key supplied to the algorithm. It must be kept secret.
data is the data which shall be encrypted/decrypted.
mode is MCRYPT_ENCRYPT or MCRYPT_DECRYPT.
iv is the optional initialization vector.
See also: mcrypt_cfb(), mcrypt_ecb(), mcrypt_ofb()
int mcrypt_cfb
(int cipher, string key, string data, int mode, string iv);mcrypt_cfb() encrypts or decrypts (depending on mode) the data with cipher and key in CFB cipher mode and returns the resulting string.
cipher is one of the MCRYPT_ciphername constants.
key is the key supplied to the algorithm. It must be kept secret.
data is the data which shall be encrypted/decrypted.
mode is MCRYPT_ENCRYPT or MCRYPT_DECRYPT.
iv is the initialization vector.
See also: mcrypt_cbc(), mcrypt_ecb(), mcrypt_ofb()
int mcrypt_ecb
(int cipher, string key, string data, int mode);mcrypt_ecb() encrypts or decrypts (depending on mode) the data with cipher and key in ECB cipher mode and returns the resulting string.
cipher is one of the MCRYPT_ciphername constants.
key is the key supplied to the algorithm. It must be kept secret.
data is the data which shall be encrypted/decrypted.
mode is MCRYPT_ENCRYPT or MCRYPT_DECRYPT.
See also: mcrypt_cbc(), mcrypt_cfb(), mcrypt_ofb()
int mcrypt_ofb
(int cipher, string key, string data, int mode, string iv);mcrypt_ofb() encrypts or decrypts (depending on mode) the data with cipher and key in OFB cipher mode and returns the resulting string.
cipher is one of the MCRYPT_ciphername constants.
key is the key supplied to the algorithm. It must be kept secret.
data is the data which shall be encrypted/decrypted.
mode is MCRYPT_ENCRYPT or MCRYPT_DECRYPT.
iv is the initialization vector.
See also: mcrypt_cbc(), mcrypt_cfb(), mcrypt_ecb()
These functions are intended to work with mhash.
This is an interface to the mhash library. mhash supports a wide variety of hash algorithms such as MD5, SHA1, GOST, and many others.
To use it, download the mhash distribution from its web site and follow the included installation instructions. You need to compile PHP with the --with-mhash parameter to enable this extension.
mhash can be used to create checksums, message digests, and more.
Example 1. Compute the SHA1 key and print it out as hex <?php $input = "Let us meet at 9 o' clock at the secret place."; $hash = mhash(MHASH_SHA1, $input); print "The hash is ".bin2hex($hash)."\n"; ?> |
The hash is d3b85d710d8f6e4e5efd4d5e67d041f9cecedafeFor a complete list of supported hashes, refer to the documentation of mhash. The general rule is that you can access the hash algorithm from PHP with MHASH_HASHNAME. For example, to access HAVAL you use the PHP constant MHASH_HAVAL.
Here is a list of hashes which are currently supported by mhash. If a hash is not listed here, but is listed by mhash as supported, you can safely assume that this documentation is outdated.
MHASH_MD5
MHASH_SHA1
MHASH_HAVAL
MHASH_RIPEMD160
MHASH_RIPEMD128
MHASH_SNEFRU
MHASH_TIGER
MHASH_GOST
MHASH_CRC32
MHASH_CRC32B
string mhash_get_hash_name
(int hash);mhash_get_hash_name() is used to get the name of the specified hash.
mhash_get_hash_name() takes the hash id as an argument and returns the name of the hash or false, if the hash does not exist.
Example 1. mhash_get_hash_name example <?php $hash = MHASH_MD5; print mhash_get_hash_name($hash); ?> |
MD5
int mhash_get_block_size
(int hash);mhash_get_block_size() is used to get the size of a block of the specified hash.
mhash_get_block_size() takes one argument, the hash and returns the size in bytes or false, if the hash does not exist.
int mhash_count
(void );mhash_count() returns the highest available hash id. Hashes are numbered from 0 to this hash id.
Example 1. Traversing all hashes <?php $nr = mhash_count(); for($i = 0; $i <= $nr; $i++) { echo sprintf("The blocksize of %s is %d\n", mhash_get_hash_name($i), mhash_get_block_size($i)); } ?> |
int connection_aborted
(void );Returns true if client disconnected. See the Connection Handling description in the Feature chapter for a complete explanation.
int connection_status
(void );Returns the connection status bitfield. See the Connection Handling description in the Feature chapter for a complete explanation.
int connection_timeout
(void );Returns true if script timed out. See the Connection Handling description in the Feature chapter for a complete explanation.
void eval
(string code_str);eval() evaluates the string given in code_str as PHP code. Among other things, this can be useful for storing code in a database text field for later execution.
There are some factors to keep in mind when using eval(). Remember that the string passed must be valid PHP code, including things like terminating statements with a semicolon so the parser doesn't die on the line after the eval(), and properly escaping things in code_str.
Also remember that variables given values under eval() will retain these values in the main script afterwards.
Example 1. eval() example - simple text merge <?php $string = 'cup'; $name = 'coffee'; $str = 'This is a $string with my $name in it.<br>'; echo $str; eval( "\$str = \"$str\";" ); echo $str; ?> |
The above example will show:
This is a $string with my $name in it. This is a cup with my coffee in it.
void die
(string message);This language construct outputs a message and terminates parsing of the script. It does not return.
Example 1. die example <?php $filename = '/path/to/data-file'; $file = fopen($filename, 'r') or die "unable to open file ($filename)"; ?> |
void exit
(void);This language construct terminates parsing of the script. It does not return.
int function_exists
(string function_name);Checks the list of defined functions for function_name. Returns true if the given function name was found, false otherwise.
int ignore_user_abort
(int [setting]);This function sets whether a client disconnect should cause a script to be aborted. It will return the previous setting and can be called without an argument to not change the current setting and only return the current setting. See the Connection Handling section in the Features chapter for a complete description of connection handling in PHP.
array iptcparse
(string iptcblock);This function parses a binary IPTC block into its single tags. It returns an array using the tagmarker as an index and the value as the value. It returns false on error or if no IPTC data was found. See GetImageSize() for a sample.
void leak
(int bytes);Leak() leaks the specified amount of memory.
This is useful when debugging the memory manager, which automatically cleans up "leaked" memory when each request is completed.
string pack
(string format, mixed [args]...);Pack given arguments into binary string according to format. Returns binary string containing data.
The idea to this function was taken from Perl and all formatting codes work the same as there. The format string consists of format codes followed by an optional repeater argument. The repeater argument can be either an integer value or * for repeating to the end of the input data. For a, A, h, H the repeat count specifies how many characters of one data argument are taken, for @ it is the absolute position where to put the next data, for everything else the repeat count specifies how many data arguments are consumed and packed into the resulting binary string. Currently implemented are
a NUL-padded string
A SPACE-padded string
h Hex string, low nibble first
H Hex string, high nibble first
c signed char
C unsigned char
s signed short (always 16 bit, machine byte order)
S unsigned short (always 16 bit, machine byte order)
n unsigned short (always 16 bit, big endian byte order)
v unsigned short (always 16 bit, little endian byte order)
i signed integer (machine dependant size and byte order)
I unsigned integer (machine dependant size and byte order)
l signed long (always 32 bit, machine byte order)
L unsigned long (always 32 bit, machine byte order)
N unsigned long (always 32 bit, big endian byte order)
V unsigned long (always 32 bit, little endian byte order)
f float (machine dependent size and representation)
d double (machine dependent size and representation)
x NUL byte
X Back up one byte
@ NUL-fill to absolute position
Example 1. pack format string $binarydata = pack("nvc*", 0x1234, 0x5678, 65, 66); The resulting binary string will be 6 bytes long and contain the byte sequence 0x12, 0x34, 0x78, 0x56, 0x41, 0x42. |
Note that the distinction between signed and unsigned values only affects the function unpack(), where as function pack() gives the same result for signed and unsigned format codes.
Also note that PHP internally stores integral values as signed values of a machine dependant size. If you give it an unsigned integral value too large to be stored that way it is converted to a double which often yields an undesired result.
int register_shutdown_function
(string func);Registers the function named by func to be executed when script processing is complete.
Common Pitfalls:
Since no output is allowed to the browser in this function, you will be unable to debug it using statements such as print or echo.
string serialize
(mixed value);serialize() returns a string containing a byte-stream representation of value that can be stored anywhere.
This is useful for storing or passing PHP values around without losing their type and structure.
To make the serialized string into a PHP value again, use unserialize(). serialize() handles the types integer, double, string, array (multidimensional) and object (object properties will be serialized, but methods are lost).
Example 1. serialize example // $session_data contains a multi-dimensional array with session // information for the current user. We use serialize() to store // it in a database at the end of the request. $conn = odbc_connect("webdb", "php", "chicken"); $stmt = odbc_prepare($conn, "UPDATE sessions SET data = ? WHERE id = ?"); $sqldata = array(serialize($session_data), $PHP_AUTH_USER); if (!odbc_execute($stmt, &$sqldata)) { $stmt = odbc_prepare($conn, "INSERT INTO sessions (id, data) VALUES(?, ?)"); if (!odbc_execute($stmt, &$sqldata)) { /* Something went wrong. Bitch, whine and moan. */ } } |
void sleep
(int seconds);The sleep function delays program execution for the given number of seconds.
See also usleep().
array unpack
(string format, string data);Unpack from binary string into array according to format. Returns array containing unpacked elements of binary string.
Unpack works slightly different from Perl as the unpacked data is stored in an associative array. To accomplish this you have to name the different format codes and separate them by a slash /.
Example 1. unpack format string $array = unpack("c2chars/nint", $binarydata); The resulting array will contain the entries "chars1", "chars2" and "int". |
For an explanation of the format codes see also: pack()
Note that PHP internally stores integral values as signed. If you unpack a large unsigned long and it is of the same size as PHP internally stored values the result will be a negative number even though unsigned unpacking was specified.
mixed unserialize
(string str);unserialize() takes a single serialized variable (see serialize()) and converts it back into a PHP value. The converted value is returned, and can be an integer, double, string, array or object. If an object was serialized, its methods are not preserved in the returned value.
Example 1. unserialize example // Here, we use unserialize() to load session data from a database // into $session_data. This example complements the one described // with serialize(). $conn = odbc_connect("webdb", "php", "chicken"); $stmt = odbc_prepare($conn, "SELECT data FROM sessions WHERE id = ?"); $sqldata = array($PHP_AUTH_USER); if (!odbc_execute($stmt, &$sqldata) || !odbc_fetch_into($stmt, &$tmp)) { // if the execute or fetch fails, initialize to empty array $session_data = array(); } else { // we should now have the serialized data in $tmp[0]. $session_data = unserialize($tmp[0]); if (!is_array($session_data)) { // something went wrong, initialize to empty array $session_data = array(); } } |
int uniqid
(string prefix);uniqid() returns a prefixed unique identifier based on current time in microseconds. The prefix can be useful for instance if you generate identifiers simultaneously on several hosts that might happen to generate the identifier at the same microsecond. The prefix can be up to 114 characters long.
If you need a unique identifier or token and you intend to give out that token to the user via the network (i.e. session cookies), it is recommended that you use something along the lines of
$token = md5(uniqid("")); // no random portion $better_token = md5(uniqid(rand())); // better, difficult to guess
This will create a 32 character identifier (a 128 bit hex number) that is extremely difficult to predict.
void usleep
(int micro_seconds);The sleep function delays program execution for the given number of micro_seconds.
See also sleep().
int msql
(string database, string query, int link_identifier);Returns a positive mSQL query identifier to the query result, or false on error.
msql() selects a database and executes a query on it. If the optional link identifier isn't specified, the function will try to find an open link to the mSQL server and if no such link is found it'll try to create one as if msql_connect() was called with no arguments (see msql_connect()).
int msql_affected_rows
(int query_identifier);Returns number of affected ("touched") rows by a specific query (i.e. the number of rows returned by a SELECT, the number of rows modified by an update, or the number of rows removed by a delete).
See also: msql_query()
int msql_close
(int link_identifier);Returns true on success, false on error.
msql_close() closes the link to a mSQL database that's associated with the specified link identifier. If the link identifier isn't specified, the last opened link is assumed.
Note that this isn't usually necessary, as non-persistent open links are automatically closed at the end of the script's execution.
msql_close() will not close persistent links generated by msql_pconnect().
See also: msql_connect() and msql_pconnect().
int msql_connect
(string hostname);Returns a positive mSQL link identifier on success, or false on error.
msql_connect() establishes a connection to a mSQL server. The hostname argument is optional, and if it's missing, localhost is assumed.
In case a second call is made to msql_connect() with the same arguments, no new link will be established, but instead, the link identifier of the already opened link will be returned.
The link to the server will be closed as soon as the execution of the script ends, unless it's closed earlier by explicitly calling msql_close().
See also msql_pconnect(), msql_close().
int msql_create_db
(string database name, int [link_identifier]
);msql_create_db() attempts to create a new database on the server associated with the specified link identifier.
See also: msql_drop_db().
int msql_createdb
(string database name, int [link_identifier]
);Identical to msql_create_db().
int msql_data_seek
(int query_identifier, int row_number);Returns true on success, false on failure.
msql_data_seek() moves the internal row pointer of the mSQL result associated with the specified query identifier to pointer to the specifyed row number. The next call to msql_fetch_row() would return that row.
See also: msql_fetch_row().
string msql_dbname
(int query_identifier, int i);msql_dbname() returns the database name stored in position i of the result pointer returned from the msql_listdbs() function. The msql_numrows() function can be used to determine how many database names are available.
int msql_drop_db
(string database_name, int link_identifier);Returns true on success, false on failure.
msql_drop_db() attempts to drop (remove) an entire database from the server associated with the specified link identifier.
See also: msql_create_db().
string msql_error
( );Errors coming back from the mSQL database backend no longer issue warnings. Instead, use these functions to retrieve the error string.
int msql_fetch_array
(int query_identifier, int
[result_type]
);Returns an array that corresponds to the fetched row, or false if there are no more rows.
msql_fetch_array() is an extended version of msql_fetch_row(). In addition to storing the data in the numeric indices of the result array, it also stores the data in associative indices, using the field names as keys.
The second optional argument result_type in msql_fetch_array() is a constant and can take the following values: MSQL_ASSOC, MSQL_NUM, and MYSQL_BOTH.
Be careful if you are retrieving results from a query that may return a record that contains only one field that has a value of 0 (or an empty string, or NULL).
An important thing to note is that using msql_fetch_array() is NOT significantly slower than using msql_fetch_row(), while it provides a significant added value.
For further details, also see msql_fetch_row()
object msql_fetch_field
(int query_identifier, int field_offset);Returns an object containing field information
msql_fetch_field() can be used in order to obtain information about fields in a certain query result. If the field offset isn't specified, the next field that wasn't yet retreived by msql_fetch_field() is retreived.
The properties of the object are:
name - column name
table - name of the table the column belongs to
not_null - 1 if the column cannot be null
primary_key - 1 if the column is a primary key
unique - 1 if the column is a unique key
type - the type of the column
See also msql_field_seek().
int msql_fetch_object
(int query_identifier, int
[result_type]
);Returns an object with properties that correspond to the fetched row, or false if there are no more rows.
msql_fetch_object() is similar to msql_fetch_array(), with one difference - an object is returned, instead of an array. Indirectly, that means that you can only access the data by the field names, and not by their offsets (numbers are illegal property names).
The optional second argument result_type in msql_fetch_array() is a constant and can take the following values: MSQL_ASSOC, MSQL_NUM, and MSQL_BOTH.
Speed-wise, the function is identical to msql_fetch_array(), and almost as quick as msql_fetch_row() (the difference is insignificant).
See also: msql_fetch_array() and msql_fetch_row().
array msql_fetch_row
(int query_identifier);Returns an array that corresponds to the fetched row, or false if there are no more rows.
msql_fetch_row() fetches one row of data from the result associated with the specified query identifier. The row is returned as an array. Each result column is stored in an array offset, starting at offset 0.
Subsequent call to msql_fetch_row() would return the next row in the result set, or false if there are no more rows.
See also: msql_fetch_array(), msql_fetch_object(), msql_data_seek(), and msql_result().
string msql_fieldname
(int query_identifier, int field);msql_fieldname() returns the name of the specified field. query_identifier is the query identifier, and field is the field index. msql_fieldname($result, 2); will return the name of the second field in the result associated with the result identifier.
int msql_field_seek
(int query_identifier, int field_offset);Seeks to the specified field offset. If the next call to msql_fetch_field() won't include a field offset, this field would be returned.
See also: msql_fetch_field().
int msql_fieldtable
(int query_identifier, int field);Returns the name of the table field was fetched from.
string msql_fieldtype
(int query_identifier, int i);msql_fieldtype() is similar to the msql_fieldname() function. The arguments are identical, but the field type is returned. This will be one of "int", "string" or "real".
string msql_fieldflags
(int query_identifier, int i);msql_fieldflags() returns the field flags of the specified field. Currently this is either, "not null", "primary key", a combination of the two or "" (an empty string).
int msql_fieldlen
(int query_identifier, int i);msql_fieldlen() returns the length of the specified field.
int msql_free_result
(int query_identifier);msql_free_result() frees the memory associated with query_identifier. When PHP completes a request, this memory is freed automatically, so you only need to call this function when you want to make sure you don't use too much memory while the script is running.
int msql_list_fields
(string database, string tablename);msql_list_fields() retrieves information about the given tablename. Arguments are the database name and the table name. A result pointer is returned which can be used with msql_fieldflags(), msql_fieldlen(), msql_fieldname(), and msql_fieldtype(). A query identifier is a positive integer. The function returns -1 if a error occurs. A string describing the error will be placed in $phperrmsg, and unless the function was called as @msql_list_fields() then this error string will also be printed out.
See also msql_error().
int msql_list_dbs
(void);msql_list_dbs() will return a result pointer containing the databases available from the current msql daemon. Use the msql_dbname() function to traverse this result pointer.
int msql_list_tables
(string database);msql_list_tables() takes a database name and result pointer much like the msql() function. The msql_tablename() function should be used to extract the actual table names from the result pointer.
int msql_num_fields
(int query_identifier);msql_num_fields() returns the number of fields in a result set.
See also: msql(), msql_query(), msql_fetch_field(), and msql_num_rows().
int msql_num_rows
(int query_identifier);msql_num_rows() returns the number of rows in a result set.
See also: msql(), msql_query(), and msql_fetch_row().
int msql_pconnect
(string hostname);Returns a positive mSQL persistent link identifier on success, or false on error.
msql_pconnect() acts very much like msql_connect() with two major differences.
First, when connecting, the function would first try to find a (persistent) link that's already open with the same host. If one is found, an identifier for it will be returned instead of opening a new connection.
Second, the connection to the SQL server will not be closed when the execution of the script ends. Instead, the link will remain open for future use (msql_close() will not close links established by msql_pconnect()).
This type of links is therefore called 'persistent'.
int msql_query
(string query, int link_identifier);msql_query() sends a query to the currently active database on the server that's associated with the specified link identifier. If the link identifier isn't specified, the last opened link is assumed. If no link is open, the function tries to establish a link as if msql_connect() was called, and use it.
Returns a positive mSQL query identifier on success, or false on error.
See also: msql(), msql_select_db(), and msql_connect().
int msql_result
(int query_identifier, int i, mixed field);Returns the contents of the cell at the row and offset in the specified mSQL result set.
msql_result() returns the contents of one cell from a mSQL result set. The field argument can be the field's offset, or the field's name, or the field's table dot field's name (fieldname.tablename). If the column name has been aliased ('select foo as bar from...'), use the alias instead of the column name.
When working on large result sets, you should consider using one of the functions that fetch an entire row (specified below). As these functions return the contents of multiple cells in one function call, they're MUCH quicker than msql_result(). Also, note that specifying a numeric offset for the field argument is much quicker than specifying a fieldname or tablename.fieldname argument.
Recommended high-performance alternatives: msql_fetch_row(), msql_fetch_array(), and msql_fetch_object().
int msql_select_db
(string database_name, int link_identifier);Returns true on success, false on error.
msql_select_db() sets the current active database on the server that's associated with the specified link identifier. If no link identifier is specified, the last opened link is assumed. If no link is open, the function will try to establish a link as if msql_connect() was called, and use it.
Every subsequent call to msql_query() will be made on the active database.
See also: msql_connect(), msql_pconnect(), and msql_query().
string msql_tablename
(int query_identifier, int field);msql_tablename() takes a result pointer returned by the msql_list_tables() function as well as an integer index and returns the name of a table. The msql_numrows() function may be used to determine the number of tables in the result pointer.
Example 1. msql_tablename() example <?php msql_connect ("localhost"); $result = msql_list_tables("wisconsin"); $i = 0; while ($i < msql_numrows($result)) { $tb_names[$i] = msql_tablename($result, $i); echo $tb_names[$i] . "<BR>"; $i++; } ?> |
int mssql_close
(int link_identifier);Returns: true on success, false on error
mssql_close() closes the link to a MS SQL Server database that's associated with the specified link identifier. If the link identifier isn't specified, the last opened link is assumed.
Note that this isn't usually necessary, as non-persistent open links are automatically closed at the end of the script's execution.
mssql_close() will not close persistent links generated by mssql_pconnect().
See also: mssql_connect(), mssql_pconnect().
int mssql_connect
(string servername, string username, string password);Returns: A positive MS SQL link identifier on success, or false on error.
mssql_connect() establishes a connection to a MS SQL server. The servername argument has to be a valid servername that is defined in the 'interfaces' file.
In case a second call is made to mssql_connect() with the same arguments, no new link will be established, but instead, the link identifier of the already opened link will be returned.
The link to the server will be closed as soon as the execution of the script ends, unless it's closed earlier by explicitly calling mssql_close().
See also mssql_pconnect(), mssql_close().
int mssql_data_seek
(int result_identifier, int row_number);Returns: true on success, false on failure
mssql_data_seek() moves the internal row pointer of the MS SQL result associated with the specified result identifier to pointer to the specifyed row number. The next call to mssql_fetch_row() would return that row.
See also: mssql_data_seek().
int mssql_fetch_array
(int result);Returns: An array that corresponds to the fetched row, or false if there are no more rows.
mssql_fetch_array() is an extended version of mssql_fetch_row(). In addition to storing the data in the numeric indices of the result array, it also stores the data in associative indices, using the field names as keys.
An important thing to note is that using mssql_fetch_array() is NOT significantly slower than using mssql_fetch_row(), while it provides a significant added value.
For further details, also see mssql_fetch_row()
object mssql_fetch_field
(int result, int field_offset);Returns an object containing field information.
mssql_fetch_field() can be used in order to obtain information about fields in a certain query result. If the field offset isn't specified, the next field that wasn't yet retreived by mssql_fetch_field() is retreived.
The properties of the object are:
name - column name. if the column is a result of a function, this property is set to computed#N, where #N is a serial number.
column_source - the table from which the column was taken
max_length - maximum length of the column
numeric - 1 if the column is numeric
See also mssql_field_seek()
int mssql_fetch_object
(int result);Returns: An object with properties that correspond to the fetched row, or false if there are no more rows.
mssql_fetch_object() is similar to mssql_fetch_array(), with one difference - an object is returned, instead of an array. Indirectly, that means that you can only access the data by the field names, and not by their offsets (numbers are illegal property names).
Speed-wise, the function is identical to mssql_fetch_array(), and almost as quick as mssql_fetch_row() (the difference is insignificant).
See also: mssql_fetch-array() and mssql_fetch-row().
array mssql_fetch_row
(int result);Returns: An array that corresponds to the fetched row, or false if there are no more rows.
mssql_fetch_row() fetches one row of data from the result associated with the specified result identifier. The row is returned as an array. Each result column is stored in an array offset, starting at offset 0.
Subsequent call to mssql_fetch_rows() would return the next row in the result set, or false if there are no more rows.
See also: mssql_fetch_array(), mssql_fetch_object(), mssql_data_seek(), mssql_fetch_lengths(), and mssql_result().
int mssql_field_seek
(int result, int field_offset);Seeks to the specified field offset. If the next call to mssql_fetch_field() won't include a field offset, this field would be returned.
See also: mssql_fetch_field().
int mssql_free_result
(int result);mssql_free_result() only needs to be called if you are worried about using too much memory while your script is running. All result memory will automatically be freed when the script, you may call mssql_free_result() with the result identifier as an argument and the associated result memory will be freed.
int mssql_num_fields
(int result);mssql_num_fields() returns the number of fields in a result set.
See also: mssql_db_query(), mssql_query(), mssql_fetch_field(), mssql_num_rows().
int mssql_num_rows
(string result);mssql_num_rows() returns the number of rows in a result set.
See also: mssql_db_query(), mssql_query() and, mssql_fetch_row().
int mssql_pconnect
(string servername, string username, string password);Returns: A positive MS SQL persistent link identifier on success, or false on error
mssql_pconnect() acts very much like mssql_connect() with two major differences.
First, when connecting, the function would first try to find a (persistent) link that's already open with the same host, username and password. If one is found, an identifier for it will be returned instead of opening a new connection.
Second, the connection to the SQL server will not be closed when the execution of the script ends. Instead, the link will remain open for future use (mssql_close() will not close links established by mssql_pconnect()).
This type of links is therefore called 'persistent'.
int mssql_query
(string query, int link_identifier);Returns: A positive MS SQL result identifier on success, or false on error.
mssql_query() sends a query to the currently active database on the server that's associated with the specified link identifier. If the link identifier isn't specified, the last opened link is assumed. If no link is open, the function tries to establish a link as if mssql_connect() was called, and use it.
See also: mssql_db_query(), mssql_select_db(), and mssql_connect().
int mssql_result
(int result, int i, mixed field);Returns: The contents of the cell at the row and offset in the specified MS SQL result set.
mssql_result() returns the contents of one cell from a MS SQL result set. The field argument can be the field's offset, or the field's name, or the field's table dot field's name (fieldname.tablename). If the column name has been aliased ('select foo as bar from...'), use the alias instead of the column name.
When working on large result sets, you should consider using one of the functions that fetch an entire row (specified below). As these functions return the contents of multiple cells in one function call, they're MUCH quicker than mssql_result(). Also, note that specifying a numeric offset for the field argument is much quicker than specifying a fieldname or tablename.fieldname argument.
Recommended high-performance alternatives: mssql_fetch_row(), mssql_fetch_array(), and mssql_fetch_object().
int mssql_select_db
(string database_name, int link_identifier);Returns: true on success, false on error
mssql_select_db() sets the current active database on the server that's associated with the specified link identifier. If no link identifier is specified, the last opened link is assumed. If no link is open, the function will try to establish a link as if mssql_connect() was called, and use it.
Every subsequent call to mssql_query() will be made on the active database.
See also: mssql_connect(), mssql_pconnect(), and mssql_query()
These functions allow you to access MySQL database servers.
More information about MySQL can be found at http://www.mysql.com/.
int mysql_affected_rows
(int [link_identifier]
);mysql_affected_rows() returns the number of rows affected by the last INSERT, UPDATE or DELETE query on the server associated with the specified link identifier. If the link identifier isn't specified, the last opened link is assumed.
If the last query was a DELETE query with no WHERE clause, all of the records will have been deleted from the table but this function will return zero.
This command is not effective for SELECT statements, only on statements which modify records. To retrieve the number of rows returned from a SELECT, use mysql_num_rows().
int mysql_close
(int [link_identifier]
);Returns: true on success, false on error
mysql_close() closes the link to a MySQL database that's associated with the specified link identifier. If the link identifier isn't specified, the last opened link is assumed.
Note that this isn't usually necessary, as non-persistent open links are automatically closed at the end of the script's execution.
mysql_close() will not close persistent links generated by mysql_pconnect().
See also: mysql_connect(), and mysql_pconnect().
int mysql_connect
(string
[hostname
[:port]
[:/path/to/socket]
]
, string [username]
, string [password]
);Returns: A positive MySQL link identifier on success, or false on error.
mysql_connect() establishes a connection to a MySQL server. All of the arguments are optional, and if they're missing, defaults are assumed ('localhost', user name of the user that owns the server process, empty password).
The hostname string can also include a port number. eg. "hostname:port" or a path to a socket eg. ":/path/to/socket" for the localhost.
Note: Support for ":port" wass added in 3.0B4.
Support for the ":/path/to/socket" was added in 3.0.10.
In case a second call is made to mysql_connect() with the same arguments, no new link will be established, but instead, the link identifier of the already opened link will be returned.
The link to the server will be closed as soon as the execution of the script ends, unless it's closed earlier by explicitly calling mysql_close().
See also mysql_pconnect(), and mysql_close().
int mysql_create_db
(string database name, int [link_identifier]
);mysql_create_db() attempts to create a new database on the server associated with the specified link identifier.
See also: mysql_drop_db(). For downwards compatibility mysql_createdb() can also be used.
int mysql_data_seek
(int result_identifier, int row_number);Returns: true on success, false on failure
mysql_data_seek() moves the internal row pointer of the MySQL result associated with the specified result identifier to point to the specified row number. The next call to mysql_fetch_row() would return that row.
int mysql_db_query
(string database, string query, int [link_identifier]
);Returns: A positive MySQL result identifier to the query result, or false on error.
mysql_db_query() selects a database and executes a query on it. If the optional link identifier isn't specified, the function will try to find an open link to the MySQL server and if no such link is found it'll try to create one as if mysql_connect() was called with no arguments
See also mysql_connect(). For downwards compatibility mysql() can also be used.
int mysql_drop_db
(string database_name, int [link_identifier]
);Returns: true on success, false on failure.
mysql_drop_db() attempts to drop (remove) an entire database from the server associated with the specified link identifier.
See also: mysql_create_db(). For downward compatibility mysql_dropdb() can also be used.
int mysql_errno
(int [link_identifier]
);Errors coming back from the mySQL database backend no longer issue warnings. Instead, use these functions to retrieve the error number.
<?php mysql_connect("marliesle"); echo mysql_errno().": ".mysql_error()."<BR>"; mysql_select_db("nonexistentdb"); echo mysql_errno().": ".mysql_error()."<BR>"; $conn = mysql_query("SELECT * FROM nonexistenttable"); echo mysql_errno().": ".mysql_error()."<BR>"; ?>
See also: mysql_error()
string mysql_error
(int [link_identifier]
);Errors coming back from the mySQL database backend no longer issue warnings. Instead, use these functions to retrieve the error string.
<?php mysql_connect("marliesle"); echo mysql_errno().": ".mysql_error()."<BR>"; mysql_select_db("nonexistentdb"); echo mysql_errno().": ".mysql_error()."<BR>"; $conn = mysql_query("SELECT * FROM nonexistenttable"); echo mysql_errno().": ".mysql_error()."<BR>"; ?>
See also: mysql_errno()
array mysql_fetch_array
(int result, int
[result_type]
);Returns an array that corresponds to the fetched row, or false if there are no more rows.
mysql_fetch_array() is an extended version of mysql_fetch_row(). In addition to storing the data in the numeric indices of the result array, it also stores the data in associative indices, using the field names as keys.
If two or more columns of the result have the same field names, the last column will take precedence. To access the other column(s) of the same name, you must the numeric index of the column or make an alias for the column.
select t1.f1 as foo t2.f1 as bar from t1, t2
An important thing to note is that using mysql_fetch_array() is NOT significantly slower than using mysql_fetch_row(), while it provides a significant added value.
The optional second argument result_type in mysql_fetch_array() is a constant and can take the following values: MYSQL_ASSOC, MYSQL_NUM, and MYSQL_BOTH.
For further details, also see mysql_fetch_row()
Example 1. mysql fetch array <?php mysql_connect($host,$user,$password); $result = mysql_db_query("database","select * from table"); while($row = mysql_fetch_array($result)) { echo $row["user_id"]; echo $row["fullname"]; } mysql_free_result($result); ?> |
object mysql_fetch_field
(int result, int [field_offset]
);Returns an object containing field information.
mysql_fetch_field() can be used in order to obtain information about fields in a certain query result. If the field offset isn't specified, the next field that wasn't yet retrieved by mysql_fetch_field() is retrieved.
The properties of the object are:
name - column name
table - name of the table the column belongs to
max_length - maximum length of the column
not_null - 1 if the column cannot be null
primary_key - 1 if the column is a primary key
unique_key - 1 if the column is a unique key
multiple_key - 1 if the column is a non-unique key
numeric - 1 if the column is numeric
blob - 1 if the column is a BLOB
type - the type of the column
unsigned - 1 if the column is unsigned
zerofill - 1 if the column is zero-filled
See also mysql_field_seek()
array mysql_fetch_lengths
(int result);Returns: An array that corresponds to the lengths of each field in the last row fetched by mysql_fetch_row(), or false on error.
mysql_fetch_lengths() stores the lengths of each result column in the last row returned by mysql_fetch_row(), mysql_fetch_array(), and mysql_fetch_object() in an array, starting at offset 0.
See also: mysql_fetch_row().
object mysql_fetch_object
(int result, int [result_typ]);Returns an object with properties that correspond to the fetched row, or false if there are no more rows.
mysql_fetch_object() is similar to mysql_fetch_array(), with one difference - an object is returned, instead of an array. Indirectly, that means that you can only access the data by the field names, and not by their offsets (numbers are illegal property names).
The optional argument result_typ is a constant and can take the following values: MYSQL_ASSOC, MYSQL_NUM, and MYSQL_BOTH.
Speed-wise, the function is identical to mysql_fetch_array(), and almost as quick as mysql_fetch_row() (the difference is insignificant).
Example 1. mysql fetch object <?php mysql_connect($host,$user,$password); $result = mysql_db_query("database","select * from table"); while($row = mysql_fetch_object($result)) { echo $row->user_id; echo $row->fullname; } mysql_free_result($result); ?> |
See also: mysql_fetch_array() and mysql_fetch_row().
array mysql_fetch_row
(int result);Returns: An array that corresponds to the fetched row, or false if there are no more rows.
mysql_fetch_row() fetches one row of data from the result associated with the specified result identifier. The row is returned as an array. Each result column is stored in an array offset, starting at offset 0.
Subsequent call to mysql_fetch_row() would return the next row in the result set, or false if there are no more rows.
See also: mysql_fetch_array(), mysql_fetch_object(), mysql_data_seek(), mysql_fetch_lengths(), and mysql_result().
string mysql_field_name
(int result, int field_index);mysql_field_name() returns the name of the specified field. Arguments to the function is the result identifier and the field index, ie. mysql_field_name($result,2);
Will return the name of the second field in the result associated with the result identifier.
For downwards compatibility mysql_fieldname() can also be used.
int mysql_field_seek
(int result, int field_offset);Seeks to the specified field offset. If the next call to mysql_fetch_field() won't include a field offset, this field would be returned.
See also: mysql_fetch_field().
string mysql_field_table
(int result, int field_offset);Get the table name for field. For downward compatibility mysql_fieldtable() can also be used.
string mysql_field_type
(int result, int field_offset);mysql_field_type() is similar to the mysql_field_name() function. The arguments are identical, but the field type is returned. This will be one of "int", "real", "string", "blob", or others as detailed in the MySQL documentation.
Example 1. mysql field types <?php mysql_connect("localhost:3306"); mysql_select_db("wisconsin"); $result = mysql_query("SELECT * FROM onek"); $fields = mysql_num_fields($result); $rows = mysql_num_rows($result); $i = 0; $table = mysql_field_table($result, $i); echo "Your '".$table."' table has ".$fields." fields and ".$rows." records <BR>"; echo "The table has the following fields <BR>"; while ($i < $fields) { $type = mysql_field_type ($result, $i); $name = mysql_field_name ($result, $i); $len = mysql_field_len ($result, $i); $flags = mysql_field_flags ($result, $i); echo $type." ".$name." ".$len." ".$flags."<BR>"; $i++; } mysql_close(); ?> |
For downward compatibility mysql_fieldtype() can also be used.
string mysql_field_flags
(int result, int field_offset);mysql_field_flags() returns the field flags of the specified field. The flags are reported as a single word per flag separated by a single space, so that you can split the returned value using explode().
The following flags are reported, if your version of MySQL is current enough to support them: "not_null", "primary_key", "unique_key", "multiple_key", "blob", "unsigned", "zerofill", "binary", "enum", "auto_increment", "timestamp".
For downward compatibility mysql_fieldflags() can also be used.
int mysql_field_len
(int result, int field_offset);mysql_field_len() returns the length of the specified field. For downward compatibility mysql_fieldlen() can also be used.
int mysql_free_result
(int result);mysql_free_result() only needs to be called if you are worried about using too much memory while your script is running. All associated result memory for the specified result identifier will automatically be freed.
For downward compatibility mysql_freeresult() can also be used.
int mysql_insert_id
(int [link_identifier]
);mysql_insert_id() returns the ID generated for an AUTO_INCREMENTED field. This function takes no arguments. It will return the auto-generated ID returned by the last INSERT query performed.
int mysql_list_fields
(string database_name, string table_name, int [link_identifier]
);mysql_list_fields() retrieves information about the given tablename. Arguments are the database name and the table name. A result pointer is returned which can be used with mysql_field_flags(), mysql_field_len(), mysql_field_name(), and mysql_field_type().
A result identifier is a positive integer. The function returns -1 if a error occurs. A string describing the error will be placed in $phperrmsg, and unless the function was called as @mysql() then this error string will also be printed out.
For downward compatibility mysql_listfields() can also be used.
int mysql_list_dbs
(int [link_identifier]
);mysql_list_dbs() will return a result pointer containing the databases available from the current mysql daemon. Use the mysql_tablename() function to traverse this result pointer.
For downward compatibility mysql_listdbs() can also be used.
int mysql_list_tables
(string database, int
[link_identifier]
);mysql_list_tables() takes a database name and returns a result pointer much like the mysql_db_query() function. The mysql_tablename() function should be used to extract the actual table names from the result pointer.
For downward compatibility mysql_listtables() can also be used.
int mysql_num_fields
(int result);mysql_num_fields() returns the number of fields in a result set.
See also: mysql_db_query(), mysql_query(), mysql_fetch_field(), mysql_num_rows().
For downward compatibility mysql_numfields() can also be used.
int mysql_num_rows
(int result);mysql_num_rows() returns the number of rows in a result set.
See also: mysql_db_query(), mysql_query() and, mysql_fetch_row().
For downward compatibility mysql_numrows() can also be used.
int mysql_pconnect
(string
[hostname
[:port]
[:/path/to/socket]
]
, string
[username]
, string
[password]
);Returns: A positive MySQL persistent link identifier on success, or false on error
mysql_pconnect() establishes a connection to a MySQL server. All of the arguments are optional, and if they're missing, defaults are assumed ('localhost', user name of the user that owns the server process, empty password).
The hostname string can also include a port number. eg. "hostname:port" or a path to a socket eg. ":/path/to/socket" for the localhost.
Note: Support for ":port" wass added in 3.0B4.
Support for the ":/path/to/socket" was added in 3.0.10.
mysql_pconnect() acts very much like mysql_connect() with two major differences.
First, when connecting, the function would first try to find a (persistent) link that's already open with the same host, username and password. If one is found, an identifier for it will be returned instead of opening a new connection.
Second, the connection to the SQL server will not be closed when the execution of the script ends. Instead, the link will remain open for future use (mysql_close() will not close links established by mysql_pconnect()).
This type of links is therefore called 'persistent'.
int mysql_query
(string query, int [link_identifier]
);mysql_query() sends a query to the currently active database on the server that's associated with the specified link identifier. If link_identifier isn't specified, the last opened link is assumed. If no link is open, the function tries to establish a link as if mysql_connect() was called with no arguments, and use it.
The query string should not end with a semicolon.
mysql_query() returns TRUE (non-zero) or FALSE to indicate whether or not the query succeeded. A return value of TRUE means that the query was legal and could be executed by the server. It does not indicate anything about the number of rows affected or returned. It is perfectly possible for a query to succeed but affect no rows or return no rows.
The following query is syntactically invalid, so mysql_query() fails and returns FALSE:
Example 1. mysql_query() <?php $result = mysql_query ("SELECT * WHERE 1=1") or die ("Invalid query"); ?> |
The following query is semantically invalid if my_col is not a column in the table my_tbl, so mysql_query() fails and returns FALSE:
Example 2. mysql_query() <?php $result = mysql_query ("SELECT my_col FROM my_tbl") or die ("Invalid query"); ?> |
mysql_query() will also fail and return FALSE if you don't have permission to access the table(s) referenced by the query.
Assuming the query succeeds, you can call mysql_affected_rows() to find out how many rows were affected (for DELETE, INSERT, REPLACE, or UPDATE statements). For SELECT statements, mysql_query() returns a new result identifier that you can pass to mysql_result(). When you are done with the result set, you can free the resources associated with it by calling mysql_free_result().
See also: mysql_affected_rows(), mysql_db_query(), mysql_free_result(), mysql_result(), mysql_select_db(), and mysql_connect().
int mysql_result
(int result, int row, mixed
[field]
);mysql_result() returns the contents of one cell from a MySQL result set. The field argument can be the field's offset, or the field's name, or the field's table dot field's name (fieldname.tablename). If the column name has been aliased ('select foo as bar from...'), use the alias instead of the column name.
When working on large result sets, you should consider using one of the functions that fetch an entire row (specified below). As these functions return the contents of multiple cells in one function call, they're MUCH quicker than mysql_result(). Also, note that specifying a numeric offset for the field argument is much quicker than specifying a fieldname or tablename.fieldname argument.
Calls mysql_result() should not be mixed with calls to other functions that deal with the result set.
Recommended high-performance alternatives: mysql_fetch_row(), mysql_fetch_array(), and mysql_fetch_object().
int mysql_select_db
(string database_name, int [link_identifier]
);Returns: true on success, false on error
mysql_select_db() sets the current active database on the server that's associated with the specified link identifier. If no link identifier is specified, the last opened link is assumed. If no link is open, the function will try to establish a link as if mysql_connect() was called, and use it.
Every subsequent call to mysql_query() will be made on the active database.
See also: mysql_connect(), mysql_pconnect(), and mysql_query()
For downward compatibility mysql_selectdb() can also be used.
string mysql_tablename
(int result, int i);mysql_tablename() takes a result pointer returned by the mysql_list_tables() function as well as an integer index and returns the name of a table. The mysql_num_rows() function may be used to determine the number of tables in the result pointer.
Example 1. mysql_tablename() example <?php mysql_connect ("localhost:3306"); $result = mysql_listtables ("wisconsin"); $i = 0; while ($i < mysql_num_rows ($result)) { $tb_names[$i] = mysql_tablename ($result, $i); echo $tb_names[$i] . "<BR>"; $i++; } ?> |