Style questions

[lvenerosy]

Granted I have never done extensive C style programming, it might be my lack of familiarity talking.

• what use is that empty struct https://github.com/pond3r/ggpo/blob/e4e11d8e3e7ff5246a935727f05801997fe2909b/src/include/ggponet.h#L79 I found some info about tagging structs but I'm not sure that's what is happening here.
• is there a reason to return a GGPOErrorCode when there is only one return value possible? Maybe for async uses?
• https://github.com/pond3r/ggpo/blob/e4e11d8e3e7ff5246a935727f05801997fe2909b/src/lib/ggpo/poll.cpp#L51 I've seen these kinds of while in a few places, and they scare me :p