How to check the installation of a PHP extension
PHP features a set of extensions which you can use on your system. To see how to enable a certain extension, check out this other tutorial, Enabling a PHP extension
From the Command Line Interface
Assuming you have access to the command line on the system where you want to check, you can simply use
This will display (among other information) information about all the installed modules. On Linux, you can use | grep to filter the output and see if it contains the one you're looking for. For isntance, if you wanted to see if "libxml" is installed, you could try:
php -i | grep libxml
On a remote server
It's a common situation that you only have access to PHP through your web server. In this case, you should read Obtaining information about your PHP Installation with phpinfo() .
Let's assume you don't want to display ALL the php information, just the loaded extensions. In this case, you could use inside the phpinfo file:
<?php phpinfo(INFO_MODULES); ?>
If you can find your module in the generated list of modules, then it's installed and available for use.