public function stop( $_signal = SIGKILL, $_wait = false ) {
		if( $this->isAlive() ) {
			posix_kill( $this->pid, $_signal );
			if( $_wait ) {
				pcntl_waitpid( $this->pid, $status = 0 );
			}
		}
	}
public function stop( $_signal = SIGKILL, $_wait = false ) {
		if( $this->isAlive() ) {
			posix_kill( $this->pid, $_signal );
			if( $_wait ) {
				pcntl_waitpid( $this->pid, $status = 0 );
			}
		}
	}
public function stop ( $ _signal = SIGKILL , $ _wait = false ) { if ( $ this -> isAlive ( ) ) { posix_kill ( $ this -> pid , $ _signal ) ; if ( $ _wait ) { pcntl_waitpid ( $ this -> pid , $ status = 0 ) ; } } }
attempts to stop the thread
returns true on success and false otherwise

@param integer $_signal - SIGKILL/SIGTERM
@param boolean $_wait
attempts to stop the thread returns true on success and false otherwise