Installation of extensions on Windows

After installing PHP and a web server on Windows, you will probably want to install some extensions for added functionality. You can choose which extensions you would like to load when PHP starts by modifying your php.ini. You can also load a module dynamically in your script using dl().

The DLLs for PHP extensions are prefixed with php_.

Many extensions are built into the Windows version of PHP. This means additional DLL files, and the extension directive, are not used to load these extensions. The Windows PHP Extensions table lists extensions that require, or used to require, additional PHP DLL files. Here's a list of built in extensions:

In PHP 4 (updated PHP 4.3.11): BCMath, Caledar, COM, Ctype, FTP, MySQL, ODBC, Overload, PCRE, Session, Tokenizer, WDDX, XML and Zlib

In PHP 5 (updated PHP 5.0.4), the following changes exist. Built in: DOM, LibXML, Iconv, SimpleXML, SPL and SQLite. And the following are no longer built in: MySQL and Overload.

The default location PHP searches for extensions is C:\php4\extensions in PHP 4 and C:\php5 in PHP 5. To change this setting to reflect your setup of PHP edit your php.ini file:

• You will need to change the extension_dir setting to point to the directory where your extensions lives, or where you have placed your php_*.dll files. For example:

  extension_dir = C:\php\extensions

• Enable the extension(s) in php.ini you want to use by uncommenting the extension=php_*.dll lines in php.ini. This is done by deleting the leading ; from the extension you want to load.

  Example 6-8. Enable Bzip2 extension for PHP-Windows // change the following line from ... ;extension=php_bz2.dll // ... to extension=php_bz2.dll

• Some of the extensions need extra DLLs to work. Couple of them can be found in the distribution package, in the C:\php\dlls\ folder in PHP 4 or in the main folder in PHP 5, but some, for example Oracle (php_oci8.dll) require DLLs which are not bundled with the distribution package. If you are installing PHP 4, copy the bundled DLLs from C:\php\dlls folder to the main C:\php folder. Don't forget to include C:\php in the system PATH (this process is explained in a separate FAQ entry).

• Some of these DLLs are not bundled with the PHP distribution. See each extensions documentation page for details. Also, read the manual section titled Installation of PECL extensions for details on PECL. An increasingly large number of PHP extensions are found in PECL, and these extensions require a separate download.

The following table describes some of the extensions available and required additional dlls.