Re: [PATCH] HP-UX does not have select.h

[Junio C Hamano <gitster@pobox.com>]

"H.Merijn Brand" <h.m.brand@xs4all.nl> writes:

> On Wed, 19 Dec 2007 11:57:21 -0800, Junio C Hamano <gitster@pobox.com> wrote:
>
>> "H.Merijn Brand" <h.m.brand@xs4all.nl> writes:
>> 
>> > On Tue, 18 Dec 2007 01:47:53 -0800, Junio C Hamano <gitster@pobox.com> wrote:
>> > ...
>> >> Merijn, discarding the earlier patch I did to configure it out for
>> >> HP-UX, does the following patch based on Andreas's idea work for you?
>> >
>> > Probably not:
>> >
>> > HP-UX 10.20, 11.00, 11.11, 11.23/PA, and 11.23/IPF all have:
>> >
>> > /usr/include 103 > grep -r POSIX_VERSION *
>> > sys/unistd.h:#    define _POSIX_VERSION _POSIX1_VERSION_88
>> > sys/unistd.h:#      define _POSIX_VERSION       _POSIX1_VERSION_90
>> > sys/unistd.h:#      define _POSIX_VERSION       _POSIX1_VERSION_93
>> > sys/unistd.h:#  define _SC_1_VERSION_88    7     /* _POSIX_VERSION: Date of POSIX.1-1988 */
>> > sys/unistd.h:#  define _SC_1_VERSION_90   102 /* _POSIX_VERSION: Date of POSIX.1-1990 */
>> > sys/unistd.h:#  define _SC_1_VERSION_93   103 /* _POSIX_VERSION: Date of POSIX.1b-1993 */
>> > sys/unistd.h:#  if (_POSIX_VERSION == _POSIX1_VERSION_88)
>> > sys/unistd.h:#    if (_POSIX_VERSION == _POSIX1_VERSION_90)
>> >
>> > and the two 11.23 do have select.h
>> 
>> Does that prove anything?  unistd.h seem to define _POSIX_VERSION to
>> various values but we do not see surrounding "#ifdef WE_DO_NOT_KNOW"
>> from the grep output above unfortunately.
>
> What I tried to demonstrate is that I have no clue about the actual value
> of this define, and if values like 88, 90, and 93 (7, 102, and 103)  do
> have any relation with the higher value of 200112L that you use.
>
> Also because these are the *only* _POSIX_VERSION defines in the entire
> include tree, and 11.23 does have a select.h, which makes the patch below
> to be not OK on 11.23. I'm not stating that HP follows the rules in any
> correct way, but if this is to be sure that select.h gets included if the
> OS supports it, it will fail.
>
>> If the folllowing actually works I think that is the cleanest fix for
>> this issue (note that I added defined(_POSIX_VERSION) there just to be
>> safe if it is not defined at all).

But your grep did not catch their definition of _POSIX1_VERSION_$YEAR
which are used to define the actual value of _POSIX_VERSION.