http://bugs.winehq.org/show_bug.cgi?id=31994
--- Comment #22 from Bruno Jesus 00cpxxx@gmail.com 2012-10-23 10:49:18 CDT --- (In reply to comment #17)
Did you broadcast to 255.255.255.255 or did you have a case like the one here? I was thinking something like that (see attachment), though it could pose problems in a multithreaded environment. I guess you could throw a critical section around it, but that sounds horrible.
You are right, I used the magic 255.255.255.255, using interface specific broadcast does NOT work in windows but also does NOT generate an error while it does in linux.
About the patch, I don't think softwares in general send data to the same socket at the same time so there should be no need for CS. And there is that problem where weird networks may not have the broadcast set to x.x.x.255 but is uncommon.
@Starous
If possible attach a wireshark debug from the game running in windows. Filter "port 55303". Maybe the packet is not even being sent.