Add ZeroMQ as network protocol

[Antonin Blot]

OpenEphys GUI uses the ZeroMQ Message Transport Protocol (ZMTP) to receive/send network event. It would nice to add that option on top of TCP/UDP.

That shouldn't be too hard, according from the example code found here: https://github.com/open-ephys/GUI/blob/master/Resources/Matlab/matlab_zeroMQ_wrapper_example.m

[Antonin Blot]

The branch UseZeroMQ in my fork works for that but is quite dirty https://bitbucket.org/blota/stimserver/branch/UseZeroMQ

I used globals at the begining of some script to decide if zeromq should be used instead of pnet. That should be replaced by a better way of setting the option (argument to startstimserver? config file?) before merging

[Dylan Muir]

I suggest adapting StartStimulusServer to change the bUseTCP argument to select whether UDP, TCP or ZMQ is used.

[Antonin Blot]

And duplicating the argument to set which protocol to use for the server and the talkback client independently? For now I use stim server with tcp but talk back to openephys with zeroMQ. I can easily switch both to zeroMQ (as my command "client" consist in 3 lines of code) if you think allowing to mix protocols for sending and receiving is a bad idea

[Dylan Muir]

Well, it’s simpler if command and talkback channels use the same protocol. Or we could specify channel URLs: “udp://127.0.0.1:port” or “tcp://127.0.0.1:port” or “zmq://127.0.0.1:port”