Mercurial > hg > octave-lojdl > gnulib-hg
diff m4/usleep.m4 @ 12315:8cb02ee162a1
usleep: new module
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>
| author | Eric Blake <ebb9@byu.net> |
|---|---|
| date | Tue, 17 Nov 2009 09:24:56 -0700 |
| parents | |
| children | c2cbabec01dd |
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new file mode 100644 --- /dev/null +++ b/m4/usleep.m4 @@ -0,0 +1,37 @@ +# usleep.m4 serial 1 +dnl Copyright (C) 2009 Free Software Foundation, Inc. +dnl This file is free software; the Free Software Foundation +dnl gives unlimited permission to copy and/or distribute it, +dnl with or without modifications, as long as this notice is preserved. + +dnl This macro intentionally does not check for select or nanosleep; +dnl both of those modules can require external libraries. +AC_DEFUN([gl_FUNC_USLEEP], +[ + AC_REQUIRE([gl_UNISTD_H_DEFAULTS]) + dnl usleep was required in POSIX 2001, but dropped as obsolete in + dnl POSIX 2008; therefore, it is not always exposed in headers. + AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) + AC_CHECK_FUNCS_ONCE([usleep]) + AC_CHECK_TYPE([useconds_t], [], + [AC_DEFINE([useconds_t], [unsigned int], [Define to an unsigned 32-bit + type if <sys/types.h> lacks this type.])]) + if test $ac_cv_func_usleep = no; then + HAVE_USLEEP=0 + AC_LIBOBJ([usleep]) + else + dnl POSIX allows implementations to reject arguments larger than + dnl 999999, but GNU guarantees it will work. + AC_CACHE_CHECK([whether usleep allows large arguments], + [gl_cv_func_usleep_works], + [AC_RUN_IFELSE([AC_LANG_PROGRAM([[ +#include <unistd.h> +]], [[return !!usleep (1000000);]])], + [gl_cv_func_usleep_works=yes], [gl_cv_func_usleep_works=no], + [gl_cv_func_usleep_works="guessing no"])]) + if test "$gl_cv_func_usleep_works" != yes; then + REPLACE_USLEEP=1 + AC_LIBOBJ([usleep]) + fi + fi +])