Different versions of PHP may have different default settings, and in the case of newer versions might have new functions. If you can’t get something to work, and think it might be because you have the wrong version of PHP there is a simple way to check. Simply running the phpinfo () function will not only tell you your PHP version but an abundance of information about all your PHP settings. Here is an example:
<?php phpinfo() ?>
Just put that single line of code in a PHP file, and run it on your server. That’s it! By running the file you should have all of the PHP information you need.