meta_leap Also note that inter-process communication is always platform dependent, at least to a degree. Using a platform-agnostic network protocol can spare you any potential gotchas there. It's also better for future scalability - for example should you wish to port to another more exotic platform or expand the thing to communicate with remote machine(s).
Even if mid level network protocol proves to be slower on a specific platform, I doubt the difference will be of any real significance if there is no need for high-volume frame-by-frame communication, as you stated is the case in the OP. So I don't see any reason to ditch the leisure and maintainability benefits of a network protocol.
But looks like this is moving into premature optimization zone now. I'd go with UDP packet exchange for start and worry about alternatives when/if it starts to cause bottlenecks.
