(PHP 5 >= 5.3.0, PHP 7) Returns status of the circular reference collector

(PHP 5 >= 5.2.1, PHP 7) Returns directory path used for temporary files

(PHP 4, PHP 5, PHP 7) Gets the inode of the current script

(PHP 4 >= 4.2.0, PHP 5, PHP 7) Gets all configuration options

(PHP 4, PHP 5) Alias of

(PHP 4 >= 4.0.1, PHP 5, PHP 7) Returns the type of interface between web server and PHP

(PHP 4, PHP 5, PHP 7) Returns an array with the names of the functions of a module

Dummy for main() There is no function named

(PHP 4 >= 4.3.0, PHP 5, PHP 7) Gets options from the command line argument list

(PHP 5, PHP 7) Returns a unique identifier for the current thread