On Thu, 24 Oct 2024 15:59:19 +1100 David Gibson <david(a)gibson.dropbear.id.au> wrote:We have a number of Makefile tests for the presence of various fields in tcp_info. However that only tells us if they're present in the kernel headers against which we're compiling, not whether they're available in the kernel we're running on. For anything outside the earliest forms of TCP_INFO (as described in netinet/tcp.h and shared with BSD), we should verify at runtime if the kernel is returning that information. This was supposed to be leading into improved handling of lazily calling TCP_INFO, but I hit additional complications there, so I've postponed it. Might as well get these bits merged, though. v2: * Previous version removed some #ifdefs that were still needed. Simply putting them back leads to awkward duplication between the "compile time missing" and "run time missing" cases, so take a different approach which allows us to remove all of them. * Some wording changesApplied with a trivial s/we here define/we define here/ and s/This taken/This is taken/ in 1/3. -- Stefano