echo ini_get("post_max_size");

This is the way you get the values of a PHP directive. It is a very handy function.
It can be used to:
* check if register globals is active on server or not: ini_get(“register_globals”)
* check what is the max upload and post size at upload: ini_get(“post_max_size”), ini_get(“upload_max_filesize”)
* check what is the max execution time for [...]