Rar is a powerful and effective archiver created by Eugene Roshal. This extension gives you possibility to read Rar archives but doesn't support writing Rar archives, because this is not supported by UnRar library and is directly prohibited by it's license.
More information about Rar and UnRar can be found at http://www.rarlabs.com/.
No external libraries are needed to build this extension.
This extension has no configuration directives defined in php.ini.
Rar is currently available through PECL http://pecl.php.net/package/rar.
Also you can use the PECL installer to install the Rar extension, using the following command: pecl -v install rar.
You can always download the tar.gz package and install Rar by hand:
Windows users can download the extension dll php_rar.dll here: http://snaps.php.net/win32/PECL_STABLE/.
There is one resource used in Rar extension: a file descriptor returned by rar_open().
This example opens a Rar file archive and extracts each entry to the specified directory.