[CC-=LKML (my mistake at start of thread; += linux-man] Hi Andreas, On Fri, Jul 25, 2008 at 11:41 AM, Andreas Jaeger <aj@xxxxxxxxxx> wrote: > "Michael Kerrisk" <mtk.manpages@xxxxxxxxx> writes: > >> [ooops -- sorry for the noise. Wrong list CCed] >> >> On 7/21/08, Michael Kerrisk <mtk.manpages@xxxxxxxxxxxxxx> wrote: >>> Andreas, >>> >>> The latest version of the page is below. >>> >>> === >>> >>> Hi Andreas, >>> >>> (Andries suggested that you probably have the background knowledge to >>> help here.) >>> >>> The math man pages in man-pages are in a somewhat sorry state, with >>> respect to the following: >>> >>> * Few of the pages properly describe the special cases for Inf, -Inf, >>> NaN arguments (e.g., compare "man 3 log" with the POSIX.1 page "man 3p >>> log"). >>> >>> * There isn't a clear discussion of error cases, and how to determine >>> if an error occurrred using errno and/or fetestexcept(3). >>> >>> I'm planning to fix each of the math man pages to address these >>> issues, and use a new page, math_error.7, as an anchor page referenced >>> by all of the math pages for discussion of how to handle errors. >>> >>> Would you be willing to review this new page (below) to see whether it >>> correctly describes the glibc details? Might you also be willing to >>> look at a sampling of the changed math page pages that I'll make later >>> this week/early next week in order to let me know I'm on the right >>> track in terms of the changes I'm making? > > In general glibc should follow the ISO C99 and Posix Standards and if > there is any discrepancy between those and the glibc implementation, > it's a bug. That should help you to verify the details as well. > > I'll try to answer questions and should be able to look at them but I > cannot double check each and every case myself. Understood. Actually, since I wrote the earlier message, I've got more confident about the direction the pages are going in anyway. See also my question in the other thread: should I provide bug reports for the discrepant cases? >>> .I math_errhandling >>> identifier, >>> which is supposed to indicate which of these two mechanisms is in use; >>> the standards require that at least one be in use, >>> but permit both to be available. >>> Although glibc does not support this identifier, >>> in practice it supports both mechanisms. > > I just noticed something that's also in draft 4, so let me cite from the > CONFORMANCE file of glibc: > > Implementing MATH_ERRNO, MATH_ERREXCEPT and math_errhandling in > <math.h> needs compiler support: see > > http://sources.redhat.com/ml/libc-hacker/2000-06/msg00008.html > http://sources.redhat.com/ml/libc-hacker/2000-06/msg00014.html > http://sources.redhat.com/ml/libc-hacker/2000-06/msg00015.html > > I check gcc and glibc and this is still missing, Yes, understood. But I had the impression that this piece is just about whether we can use math_errhandling to determine which of errno or fetestexcept() can be used to check for errors. Glibc doesn't provide math_errhandling, but the tendency seems to be that both mechanisms are supported, with a few discrepancies. -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ man-pages online: http://www.kernel.org/doc/man-pages/online_pages.html Found a bug? http://www.kernel.org/doc/man-pages/reporting_bugs.html -- To unsubscribe from this list: send the line "unsubscribe linux-man" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
