recv_match() error over UDP connection

[jordancormack]

I've been using pymavlink to successfully send and receive mavlink messages using a serial connection, and I am trying to move to UDP.

When I try to receive a message using msg = master.recv_match() I get the following error:

"data, new_addr = self.port.recvfrom(UDP_MAX_PACKET_LEN)
OSError: [WinError 10022] An invalid argument was supplied"

However, if I send a message immediately before (e.g. master.mav.heartbeat_send(...) I don't get an error, and a burst of messages are successfully received, before a pause, and another burst of messages.