(PECL runkit >= 0.7.0) Remove/Delete an already defined constant

(PECL runkit >= 0.7.0) Copy a function to a new function name

(PECL runkit >= 0.7.0) Change a function's name

(PHP 4 >= 4.3.0, PHP 5, PHP 7) Generates a backtrace

(PHP 4, PHP 5, PHP 7) Sets which PHP errors are reported

(PHP 4, PHP 5, PHP 7) Gets time of last page modification

(PHP 4, PHP 5, PHP 7) Gets PHP's process ID int

(PECL apcu >= 4.0.0) Clears the APCu cache

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

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