Reactor stop with exit code.

gistfile1.txt

    def _exit(self, exit_code=0):
        """
        Helper method for testing.

        Use os._exit() to avoid re-raising SystemExit error.

        When reactor is running add a hook to be called after reactor stop.

        This is mocked in tests since we can not addSystemEventTrigger
        multiple times for the same reactor.
        """
        def shutdown():
            Logger.shutdown()
            os._exit(exit_code)

        if reactor.running:
            reactor.addSystemEventTrigger(
                'before', 'shutdown', self.stopServices)
            reactor.addSystemEventTrigger('after', 'shutdown', shutdown)
            reactor.stop()
        else:
            shutdown()