mingw usleep(1000000) failed with EINVAL, as allowed by POSIX,
but contrary to GNU usage. Rather than implement an accurate
usleep based on select or nanosleep, both of which drag in
dependencies on external libraries, this version intentionally
takes the ceiling in seconds if usleep() is missing.
* modules/usleep: New file.
* m4/usleep.m4 (gl_FUNC_USLEEP): Likewise.
* lib/usleep.c (usleep): Likewise.
* m4/unistd_h.m4 (gl_UNISTD_H_DEFAULTS): Add defaults.
* modules/unistd (Makefile.am): Substitute witnesses.
* lib/unistd.in.h (usleep): Add declaration.
* doc/pastposix-functions/usleep.texi (usleep): Document this.
* MODULES.html.sh (Date and time): Likewise.
* modules/usleep-tests (Depends-on): New test.
* tests/test-usleep.c: New file.
Signed-off-by: Eric Blake <ebb9@byu.net>
Newer mingw has usleep, but it rejects arguments over 1000000
without sleeping. And since stat has no visibility into
sub-second resolutions, it meant all the timestamps ended up
identical. Fixed by restoring the 8 seconds of sleep, as
well as working around the documented unlink issue.
* tests/test-stat-time.c (force_unlink): Return a value.
(test_ctime) [W32]: Fix compilation error.
(nap): Don't call usleep with too large an argument. Use
force_unlink.
* doc/pastposix-functions/usleep.texi (usleep): Document the
portability issue.
Signed-off-by: Eric Blake <ebb9@byu.net>
