Thanks very much for the reply - I will wait for Corinna's take on this as well - the patch shouldn't be too hard.
In fact the source code for curl in the lib/connect.c file has code to enable the winsock options, so hopefully that code could be helpful. I imagine there must be a translation between the POSIX sockets and winsock in the fhandler_socket. I will attempt to download the cygwin source code - I've never built it, so I don't know how hard it will be. I am surprised that no one else has ever needed the low level TCP keep alives to work. On Sun, Jun 7, 2020 at 2:21 PM Ken Brown via Cygwin <cygwin@cygwin.com> wrote: > On 6/7/2020 9:20 AM, Cary Lewis via Cygwin wrote: > > These constants are usually defined in netinet/tcp.h but are not defined > > anywhere in cygwin. > > > > As a result there does not seem to be a way to enable the socket level > keep > > alives in cygwin. > > > > One result of this is curl's --keepalive-time option does not work, but > it > > would affect any attempt to enable socket keep alives. > > > > Windows' sockets do support keep alives, and indeed the win32 version of > > curl works correctly. > > > > Can someone explain why the TCP keep alive constants are not defined > > I'm not an expert on sockets, but I'll just make a couple of comments > until > Corinna has a chance to give a definitive reply. > > Cygwin's netinet/tcp.h was derived from the FreeBSD version of the file > dated > 2000/01/09. It has hardly been touched since it was imported into Cygwin > in > 2002. FreeBSD didn't add keepalive support until 2012. > > > Is it possible to add this functionality? > > If you're asking someone else to do it, the question is whether one of the > Cygwin developers has the time and expertise to do it. If you're > volunteering > to do it, patches are always welcome. > > > Where in the cygwin source code does the actual posix socket to winsock > > translation take place? > > Cygwin's socket support is in the fhandler_socket* files. > > Ken > -- > Problem reports: https://cygwin.com/problems.html > FAQ: https://cygwin.com/faq/ > Documentation: https://cygwin.com/docs.html > Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple > -- Problem reports: https://cygwin.com/problems.html FAQ: https://cygwin.com/faq/ Documentation: https://cygwin.com/docs.html Unsubscribe info: https://cygwin.com/ml/#unsubscribe-simple
