Hi ALex, On 1/8/21 12:14 PM, Alejandro Colomar (man-pages) wrote: > Hi Michael, > > On 1/8/21 11:50 AM, Michael Kerrisk (man-pages) wrote: >> Hi Alex, >> >> On 1/7/21 6:04 PM, Alejandro Colomar (man-pages) wrote: >>> Hi Michael, >>> >>> [[ >>> SYNOPSIS >>> #include <stdlib.h> >>> >>> int clearenv(void); >>> >>> Feature Test Macro Requirements for glibc (see fea‐ >>> ture_test_macros(7)): >>> >>> clearenv(): >>> /* Glibc since 2.19: */ _DEFAULT_SOURCE >>> || /* Glibc <= 2.19: */ _SVID_SOURCE || _BSD_SOURCE >>> >>> ]] >>> >>> [[ >>> SYNOPSIS >>> #include <time.h> >>> >>> int dysize(int year); >>> >>> Feature Test Macro Requirements for glibc (see fea‐ >>> ture_test_macros(7)): >>> >>> dysize(): >>> Since glibc 2.19: >>> _DEFAULT_SOURCE >>> Glibc 2.19 and earlier: >>> _BSD_SOURCE || _SVID_SOURCE >>> >>> ]] >>> >>> Which one do you prefer? >> >> Probably the latter, since it is a little easier to read. >> >> The former form has crept in as a result of my attempts >> to keep the FTM info somewhat compact. See, for example: >> >> chroot(): >> Since glibc 2.2.2: >> _XOPEN_SOURCE && ! (_POSIX_C_SOURCE >= 200112L) >> || /* Since glibc 2.20: */ _DEFAULT_SOURCE >> || /* Glibc <= 2.19: */ _BSD_SOURCE >> Before glibc 2.2.2: >> none >> >> >> waitid(): >> Since glibc 2.26: >> _XOPEN_SOURCE >= 500 || _POSIX_C_SOURCE >= 200809L >> Glibc 2.25 and earlier: >> _XOPEN_SOURCE >> || /* Since glibc 2.12: */ _POSIX_C_SOURCE >= 200809L >> || /* Glibc <= 2.19: */ _BSD_SOURCE >> >> The latter could be rewritten (I hope I got the expansion right) >> as: >> waitid(): >> Since glibc 2.26: >> _XOPEN_SOURCE >= 500 || _POSIX_C_SOURCE >= 200809L >> Glibc 2.20 to 2.25 >> _XOPEN_SOURCE || _POSIX_C_SOURCE >= 200809L >> Glibc 2.12 to 2.19 >> _XOPEN_SOURCE || _POSIX_C_SOURCE >= 200809L >> || _BSD_SOURCE >> Glibc 2.11 and earlier: >> _XOPEN_SOURCE || _BSD_SOURCE >> >> >> That's more verbose, but perhaps also easier to read, now that >> I look at it. >> >> I'm not sure whether you are thinking of doing some global edit, >> but if you are, perhaps we need to discuss this more. > > Well, I'm not thinking of a global edit right now (we've had enough of > those for now I think :), but more as something to think for the future. > So yes, a discussion about if we prefer to have a single way of > expressing FTM or if there are times when the other way is better would > be good. > Your thoughts? On reflection, I think the final form that I have shown may be preferable. Thanks, Michael -- Michael Kerrisk Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/ Linux/UNIX System Programming Training: http://man7.org/training/
