On Jul 10 03:19, Sam Mani wrote: > What header should a C file include to be able to call gethostbyname2() ? In theory that would be netdb.h, but apparently we forgot to declare the function there and nobody missed it so far. I applied a patch to CVS so the declaration will be added to the next Cygwin release. For the time being, just declare the function in your source file, in C++ for instance: extern "C" struct hostent *gethostbyname2 (const char *, int); Corinna -- Corinna Vinschen Please, send mails regarding Cygwin to Cygwin Project Co-Leader cygwin AT cygwin DOT com Red Hat -- 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