Function handler

imperative/python/megengine/data/signal_handling.py:21–25

(signum, frame)

        previous_handler = None

    def handler(signum, frame):
        _check_any_worker_failed()
        if previous_handler is not None:
            assert callable(previous_handler)
            previous_handler(signum, frame)

    signal.signal(signal.SIGCHLD, handler)
    _sigchld_handler_set = True