Mercurial > gnulib
view m4/utimensat.m4 @ 40196:e63f5d3edab5
relocatable-prog: Update documentation.
* doc/relocatable-maint.texi (Supporting Relocation): Update to match
the recent changes.
author | Bruno Haible <bruno@clisp.org> |
---|---|
date | Sun, 24 Feb 2019 01:49:15 +0100 |
parents | b06060465f09 |
children |
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# serial 6 # See if we need to provide utimensat replacement. dnl Copyright (C) 2009-2019 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. # Written by Eric Blake. AC_DEFUN([gl_FUNC_UTIMENSAT], [ AC_REQUIRE([gl_SYS_STAT_H_DEFAULTS]) AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) AC_CHECK_FUNCS_ONCE([utimensat]) if test $ac_cv_func_utimensat = no; then HAVE_UTIMENSAT=0 else AC_CACHE_CHECK([whether utimensat works], [gl_cv_func_utimensat_works], [AC_RUN_IFELSE( [AC_LANG_PROGRAM([[ #include <fcntl.h> #include <sys/stat.h> #include <unistd.h> ]], [[int result = 0; const char *f = "conftest.file"; if (close (creat (f, 0600))) return 1; /* Test whether the AT_SYMLINK_NOFOLLOW flag is supported. */ { if (utimensat (AT_FDCWD, f, NULL, AT_SYMLINK_NOFOLLOW)) result |= 2; } /* Test whether UTIME_NOW and UTIME_OMIT work. */ { struct timespec ts[2]; ts[0].tv_sec = 1; ts[0].tv_nsec = UTIME_OMIT; ts[1].tv_sec = 1; ts[1].tv_nsec = UTIME_NOW; if (utimensat (AT_FDCWD, f, ts, 0)) result |= 4; } sleep (1); { struct stat st; struct timespec ts[2]; ts[0].tv_sec = 1; ts[0].tv_nsec = UTIME_NOW; ts[1].tv_sec = 1; ts[1].tv_nsec = UTIME_OMIT; if (utimensat (AT_FDCWD, f, ts, 0)) result |= 8; if (stat (f, &st)) result |= 16; else if (st.st_ctime < st.st_atime) result |= 32; } return result; ]])], [gl_cv_func_utimensat_works=yes], [gl_cv_func_utimensat_works=no], [gl_cv_func_utimensat_works="guessing yes"])]) if test "$gl_cv_func_utimensat_works" = no; then REPLACE_UTIMENSAT=1 fi fi ])