comparison mercurial/worker.py @ 49230:5d28246b9acc

worker: explain why pickle reading stream has to be unbuffered

49229:ed9170ff791a

                    os._exit(ret & 255)
        pids.add(pid)
    selector = selectors.DefaultSelector()
    for rfd, wfd in pipes:
        os.close(wfd)
        selector.register(os.fdopen(rfd, 'rb', 0), selectors.EVENT_READ)

    def cleanup():
        signal.signal(signal.SIGINT, oldhandler)
        waitforworkers()

49230:5d28246b9acc

                    os._exit(ret & 255)
        pids.add(pid)
    selector = selectors.DefaultSelector()
    for rfd, wfd in pipes:
        os.close(wfd)
        # The stream has to be unbuffered. Otherwise, if all data is read from
        # the raw file into the buffer, the selector thinks that the FD is not
        # ready to read while pickle.load() could read from the buffer. This
        # would delay the processing of readable items.
        selector.register(os.fdopen(rfd, 'rb', 0), selectors.EVENT_READ)

    def cleanup():
        signal.signal(signal.SIGINT, oldhandler)
        waitforworkers()