(PHP 4, PHP 5, PHP 7) Gets the current PHP version

(PHP 5, PHP 7 >= 5.5.0, PHP 7) Sets the process title

(PHP 4, PHP 5, PHP 7) Returns an array with the names of included or required files

(PHP 4, PHP 5, PHP 7) Gets the version of the current Zend engine

(PHP 4, PHP 5, PHP 7) Set/get the various assert flags

(PHP 4, PHP 5, PHP 7) Returns an array with the names of all modules compiled and loaded

(PHP 4, PHP 5, PHP 7) Gets the value of an environment variable

(PHP 5 >= 5.3.0, PHP 7) Activates the circular reference collector

(PHP 4 >= 4.3.0, PHP 5, PHP 7) Gets the current include_path configuration option

(PHP 5 >= 5.2.0, PHP 7) Returns the peak of memory allocated by PHP