protected function ipc_init()
	{
		// windows needs AF_INET
		$domain = strtoupper(substr(PHP_OS, 0, 3)) == 'WIN' ? AF_INET : AF_UNIX;

		// create a socket pair for IPC
		$sockets = array();
		if (socket_create_pair($domain, SOCK_STREAM, 0, $sockets) === false)
		{
			$this->log('socket_create_pair failed: ' . socket_strerror(socket_last_error()), self::LOG_LEVEL_CRIT);
			return false;
		}

		// return the sockets
		return $sockets;
	}