Thanks I am experiencing some trouble though. As I understand it, what I want is: #pargma pack(nopack)But that is apparently not supported in gcc. I get the following warning: warning: unknown action 'nopack' for '#pragma pack' - ignored I can reduce the size to 10 by using #pargma pack(1)but that is still not the size I would expect. I could, however, just ignore the extra bytes when sending my packets, but how should I the go about filling a struct with data from an incomming packet? What should I do about the extra bytes in the struct?