selector_events.py 文件源码

def sendto(self, data, addr=None):
        if not isinstance(data, (bytes, bytearray, memoryview)):
            raise TypeError('data argument must be byte-ish (%r)',
                            type(data))
        if not data:
            return

        if self._address and addr not in (None, self._address):
            raise ValueError('Invalid address: must be None or %s' %
                             (self._address,))

        if self._conn_lost and self._address:
            if self._conn_lost >= constants.LOG_THRESHOLD_FOR_CONNLOST_WRITES:
                logger.warning('socket.send() raised exception.')
            self._conn_lost += 1
            return

        if not self._buffer:
            # Attempt to send it right away first.
            try:
                if self._address:
                    self._sock.send(data)
                else:
                    self._sock.sendto(data, addr)
                return
            except (BlockingIOError, InterruptedError):
                self._loop.add_writer(self._sock_fd, self._sendto_ready)
            except OSError as exc:
                self._protocol.error_received(exc)
                return
            except Exception as exc:
                self._fatal_error(exc,
                                  'Fatal write error on datagram transport')
                return

        # Ensure that what we buffer is immutable.
        self._buffer.append((bytes(data), addr))
        self._maybe_pause_protocol()