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

(PECL weakref >= 0.2.0) Returns the value pointed to by a certain object

(PECL apc >= 3.1.1) Updates an old value with a new value

(PECL weakref >= 0.2.0) Rewinds the iterator to the beginning of the map

(PECL apc >= 2.0.0) Retrieves APC's Shared Memory Allocation information

(PECL apcu >= 5.0.0) Get total count public

(PECL apd >= 0.2) Overrides built-in functions

(PECL apd 0.2-0.4) Returns the current call stack as an array

(PHP 7) Reclaims memory used by the Zend Engine memory manager

(PECL runkit >= 0.7.0) Check the PHP syntax of the specified file