runtime.py 文件源码

def register_signal(signal_number, handler_func, once = False):
    prev_handler = None

    def _handler(signum, frame):
        skip_prev = handler_func(signum, frame)

        if not skip_prev:
            if callable(prev_handler):
                if once:
                    signal.signal(signum, prev_handler)
                prev_handler(signum, frame)
            elif prev_handler == signal.SIG_DFL and once:
                signal.signal(signum, signal.SIG_DFL)
                os.kill(os.getpid(), signum)

    prev_handler = signal.signal(signal_number, _handler)