mdns fails with OSError: No such device

[edwardpier]

My WebRTC session failed when trying to connect over a Raspberry Pi with its wifi configured as a base station. The aioice code threw an OSError with message No such device from mdns.py line 175. This is the call to rx_sock.setsockopt.

A little googling indicated that this might be because the network interface could not do multicast. While this might be solved by reconfiguring my networking, it would be best if the aioice code could handle multicast failures gracefully and skip candidates that have a .local hostname.

I hacked the code to catch the OSError. If you like, I can make a pull request, but I feel that my hack is a bit inelegant and could be done better by the original code author without much effort.

Please let me know if you would like more information or if there is anything I can do to help. I appreciate the effort that has gone into this really useful package.