Back to the list, and please keep replies there. >> There are (of course) a lot of other included files, and > <sys/select.h> is one of them. In my code it comes AFTER the > redefinition of FD_SETSIZE and <sys/types.h>. I don't think this > could be the issue. It is if you are mixing Windows API and Cygwin. Just look at sys/select.h and you'll understand. -- René Berber -- Problem reports: http://cygwin.com/problems.html FAQ: http://cygwin.com/faq/ Documentation: http://cygwin.com/docs.html Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple