Method register

Lib/selectors.py:238–249

(self, fileobj, events, data=None)

            raise

    def register(self, fileobj, events, data=None):
        if (not events) or (events & ~(EVENT_READ | EVENT_WRITE)):
            raise ValueError("Invalid events: {!r}".format(events))

        key = SelectorKey(fileobj, self._fileobj_lookup(fileobj), events, data)

        if key.fd in self._fd_to_key:
            raise KeyError("{!r} (FD {}) is already registered"
                           .format(fileobj, key.fd))

        self._fd_to_key[key.fd] = key
        return key

    def unregister(self, fileobj):
        try: