On Tue, Nov 5, 2024 at 4:33 AM Alejandro Colomar <alx@xxxxxxxxxx> wrote: > On Mon, Nov 04, 2024 at 09:53:38PM GMT, Kuniyuki Iwashima wrote: > > From: Alex Henrie <alexhenrie24@xxxxxxxxx> > > Date: Mon, 4 Nov 2024 21:14:20 -0700 > > > struct ifa_cacheinfo contains the address's creation time, update time, > > > preferred lifetime, and valid lifetime. See > > We use two spaces after period (the correct amount). :) > (I'm thinking we probably want to document something about it in > man-pages(7). Branden, do you want to send a patch about it? I want > to include the references you showed to me, and you probably remember > better those links.) > > > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/uapi/linux/if_addr.h?h=v6.11#n60 > > Please use this format for links: > > Link: <http://example.com> Since the second sentence will be eliminated in favor of a Link line, the first sentence will no longer have any spaces after its period. > Which include provides the structure? linux/if_addr.h, which is the file I linked to in the commit message, and the same file that contains struct ifaddrmsg which is documented a few paragraphs earlier in the same section of the man page. > > > +struct ifa_cacheinfo { > > > + __u32 ifa_prefered; /* Preferred lifetime in seconds, -1 = forever */ > > > + __u32 ifa_valid; /* Valid lifetime in seconds, -1 = forever */ > > > > -1 should be rather 0xFFFFFFFF (INFINITY_LIFE_TIME) as it's unsigned. > > I prefer UINT32_MAX over 0xF...F, which might be unclear how many Fs it > has. INFINITY_LIFE_TIME is not defined in any public header, so let's not mention it. I agree that it's hard to see at a glance how many F's are in 0xFFFFFFFF. I would suggest ~0u, which is short and sweet, but UINT32_MAX is a little better because ~0u isn't 32 bits on all C compilers that have ever existed. > > Also, it would be nice to mention that ifa_prefered must be less than > > or equal to ifa_valid (ifa_prefered <= ifa_valid) and 0 is invalid for > > ifa_valid. > > > > 0 <= ifa_prefered <= ifa_valid > > 0 < ifa_valid <= 0xFFFFFFFF I'll add a paragraph to explain those relationships. > It might also be interesting to add a separate manual page for the type, > and reference it here. Otherwise, the page starts getting fatty. Perhaps. In my opinion, there's not enough material here to be worthy of its own page. Thanks for the feedback, -Alex
