On Jun 7 14:56, Cary Lewis via Cygwin wrote: > Thanks very much for the reply - I will wait for Corinna's take on this as > well - the patch shouldn't be too hard.
It's not that easy, but not too hard either: - Windows 10 1709 and later actually support the TCP_KEEPIDLE, TCP_KEEPINTVL and TCP_KEEPCNT options natively, so all is fine here. - Older OS versions require the use of a single call WSAIoctl(SIO_KEEPALIVE_VALS), while TCP_KEEPIDLE, TCP_KEEPINTVL and TCP_KEEPCNT are three distinct calls, with TCP_KEEPCNT being no-op on pre W10 1709. > 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 But, here's the question: Even if neither one of SIO_KEEPALIVE_VALS, TCP_KEEPIDLE, TCP_KEEPINTVL and TCP_KEEPCNT are available, curl *still* uses SO_KEEPALIVE to enable TCP keep-alive. Given TCP keep-alive has default settings on Windows, too (2 hours, 1 sec, 10 times), and given SO_KEEPALIVE is supported on Cygwin as well, why isn't that sufficient? Keep in mind that none of the above WSAIoctl/setsockopt options are portable, only SO_KEEPALIVE is. So why should that work on, say, Solaris, but not on Windows? Corinna -- Corinna Vinschen Cygwin Maintainer -- 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
