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

(PECL apc >= 3.1.1) Deletes files from the opcode cache

(PECL apd 0.2) Get an array of the current variables names in the local scope

(PECL wincache >= 1.0.0) Retrieves information about opcode cache memory usage

(PECL uopz >= 1.0.3) Backup a function void

(PECL apc >= 3.1.4) Checks if APC key exists

(PECL wincache >= 1.1.0) Acquires an exclusive lock on a given key

(PHP 4, PHP 5, PHP 7) Gets the current configuration setting of magic_quotes_gpc

(PECL apc >= 3.1.1) Decrease a stored number

(PECL uopz >= 1.0.0) Compose a class void