Here is an email from the DBD:pg guys describing what _GNU_SOURCE does.
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Jeroen Ruigrok/asmodai wrote:
> It's a glibc thing.
>
> Look at glibc's include/features.h:
>
> _GNU_SOURCE All of the above, plus GNU extensions.
>
> Which means it enables all this:
>
> __STRICT_ANSI__, _ISOC99_SOURCE, _POSIX_SOURCE, _POSIX_C_SOURCE,
> _XOPEN_SOURCE, _XOPEN_SOURCE_EXTENDED, _LARGEFILE_SOURCE,
> _LARGEFILE64_SOURCE, _FILE_OFFSET_BITS=N, _BSD_SOURCE, _SVID_SOURCE
>
> --
> Jeroen Ruigrok van der Werven <asmodai(at)wxs.nl> / asmodai / kita no mono
> PGP fingerprint: 2D92 980E 45FE 2C28 9DB7 9D88 97E6 839B 2EAC 625B
> http://www.tendra.org/ | http://www.in-nomine.org/~asmodai/diary/
> There is no greater sorrow than to recall, in misery, the time when we
> were happy...
>
-- Bruce Momjian | http://candle.pha.pa.us pgman@candle.pha.pa.us | (610)
359-1001+ If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square,
Pennsylvania19073
