*/ interface ProcessControlInterface { /** Checks if a process exists. * * @param int $pid The process identifier. * * @return boolean true is the process is running, else false. */ public function isRunning($pid); /** Terminate a running process. * * @param int $pid The process identifier. * @param bool $forcefully Whether to gently (false) or forcefully (true) terminate the process. */ public function kill($pid, $forcefully = false); }