--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,19 @@
 2009-10-10  Eric Blake  <ebb9@byu.net>
 
+	futimens: new module
+	* modules/futimens: New file.
+	* lib/futimens.c (futimens): Likewise.
+	* m4/futimens.m4 (gl_FUNC_FUTIMENS): Likewise.
+	* lib/utimens.c (futimens): Avoid recursion into rpl_futimens, so
+	we can work around Linux bugs.
+	* m4/sys_stat_h.m4 (gl_SYS_STAT_H_DEFAULTS): Add witnesses.
+	* modules/sys_stat (Makefile.am): Substitute them.
+	* lib/sys_stat.in.h (futimens): Declare it.
+	* MODULES.html.sh (systems lacking POSIX:2008): Mention module.
+	* doc/posix-functions/futimens.texi (futimens): Likewise.
+	* modules/futimens-tests: New test.
+	* tests/test-futimens.c: Likewise.
+
 	utimens: introduce fdutimens
 	* lib/utimens.h (fdutimens): New prototype.
 	* lib/utimens.c (gl_futimens): Move guts...

--- a/MODULES.html.sh
+++ b/MODULES.html.sh
@@ -2262,6 +2262,7 @@
   func_module ftell
   func_module ftello
   func_module ftruncate
+  func_module futimens
   func_module getaddrinfo
   func_module getcwd
   func_module getgroups

--- a/doc/posix-functions/futimens.texi
+++ b/doc/posix-functions/futimens.texi
@@ -4,14 +4,10 @@
 
 POSIX specification: @url{http://www.opengroup.org/onlinepubs/9699919799/functions/futimens.html}
 
-Gnulib module: ---
+Gnulib module: futimens
 
 Portability problems fixed by Gnulib:
 @itemize
-@end itemize
-
-Portability problems not fixed by Gnulib:
-@itemize
 @item
 This function is missing on some platforms:
 glibc 2.3.6, MacOS X 10.3, FreeBSD 6.0, NetBSD 3.0, OpenBSD 3.8, AIX
@@ -26,9 +22,12 @@
 the @code{tv_sec} argument to be 0, and don't necessarily handle all
 file permissions in the manner required by POSIX:
 Linux kernel 2.6.25.
+@end itemize
+
+Portability problems not fixed by Gnulib:
+@itemize
 @item
 Some platforms lack the ability to change the timestamps of a file
-descriptor, so this function can fail with @code{ENOSYS}.
+descriptor, so the replacement can fail with @code{ENOSYS}; the gnulib
+module @samp{utimens} provides a more reliable interface @code{gl_futimens}.
 @end itemize
-
-The gnulib module utimens provides a similar interface.

new file mode 100644
--- /dev/null
+++ b/lib/futimens.c
@@ -0,0 +1,37 @@
+/* Set the access and modification time of an open fd.
+   Copyright (C) 2009 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* written by Eric Blake */
+
+#include <config.h>
+
+#include <sys/stat.h>
+
+#include "utimens.h"
+
+/* Set the access and modification time stamps of FD to be
+   TIMESPEC[0] and TIMESPEC[1], respectively.
+   Fail with ENOSYS on systems without futimes (or equivalent).
+   If TIMESPEC is null, set theh time stamps to the current time.
+   Return 0 on success, -1 (setting errno) on failure.  */
+int
+futimens (int fd, const struct timespec times[2])
+{
+  /* fdutimens also works around bugs in native futimens, when running
+     with glibc compiled against newer headers but on a Linux kernel
+     older than 2.6.26.  */
+  return fdutimens (NULL, fd, times);
+}

--- a/lib/sys_stat.in.h
+++ b/lib/sys_stat.in.h
@@ -355,6 +355,23 @@
 #endif
 
 
+#if @GNULIB_FUTIMENS@
+# if @REPLACE_FUTIMENS@
+#  undef futimens
+#  define futimens rpl_futimens
+# endif
+# if !@HAVE_FUTIMENS@ || @REPLACE_FUTIMENS@
+extern int futimens (int fd, struct timespec const times[2]);
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef futimens
+# define futimens(f,t)                         \
+    (GL_LINK_WARNING ("futimens is not portable - " \
+                      "use gnulib module futimens for portability"), \
+     futimens (f, t))
+#endif
+
+
 #if @GNULIB_MKDIRAT@
 # if !@HAVE_MKDIRAT@
 extern int mkdirat (int fd, char const *file, mode_t mode);

--- a/lib/utimens.c
+++ b/lib/utimens.c
@@ -49,6 +49,9 @@
 };
 #endif
 
+/* Avoid recursion with rpl_futimens.  */
+#undef futimens
+
 /* Validate the requested timestamps.  Return 0 if the resulting
    timespec can be used for utimensat (after possibly modifying it to
    work around bugs in utimensat).  Return 1 if the timespec needs

new file mode 100644
--- /dev/null
+++ b/m4/futimens.m4
@@ -0,0 +1,41 @@
+# serial 1
+# See if we need to provide futimens replacement.
+
+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.
+
+# Written by Eric Blake.
+
+AC_DEFUN([gl_FUNC_FUTIMENS],
+[
+  AC_REQUIRE([gl_SYS_STAT_H_DEFAULTS])
+  AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+  AC_CHECK_FUNCS_ONCE([futimens])
+  if test $ac_cv_func_futimens = no; then
+    HAVE_FUTIMENS=0
+    AC_LIBOBJ([futimens])
+  else
+    AC_CACHE_CHECK([whether futimens works],
+      [gl_cv_func_futimens_works],
+      [AC_RUN_IFELSE([AC_LANG_PROGRAM([[
+#include <fcntl.h>
+#include <sys/stat.h>
+#ifdef __linux__
+/* The Linux kernel added futimens in 2.6.22, but it had bugs until 2.6.26.
+   Always replace futimens to support older kernels.  */
+choke me
+#endif
+]], [[struct timespec ts[2] = { { 1, UTIME_OMIT }, { 1, UTIME_OMIT } };
+      if (futimens (AT_FDCWD, NULL)) return 1;
+      return futimens (open (".", O_RDONLY), ts);]])],
+         [gl_cv_func_futimens_works=yes],
+         [gl_cv_func_futimens_works="needs runtime check"],
+         [gl_cv_func_futimens_works="guessing no"])])
+    if test "$gl_cv_func_futimens_works" != yes; then
+      REPLACE_FUTIMENS=1
+      AC_LIBOBJ([futimens])
+    fi
+  fi
+])

--- a/m4/sys_stat_h.m4
+++ b/m4/sys_stat_h.m4
@@ -1,4 +1,4 @@
-# sys_stat_h.m4 serial 17   -*- Autoconf -*-
+# sys_stat_h.m4 serial 18   -*- Autoconf -*-
 dnl Copyright (C) 2006-2009 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -41,6 +41,7 @@
   AC_REQUIRE([gl_UNISTD_H_DEFAULTS]) dnl for REPLACE_FCHDIR
   GNULIB_FCHMODAT=0;  AC_SUBST([GNULIB_FCHMODAT])
   GNULIB_FSTATAT=0;   AC_SUBST([GNULIB_FSTATAT])
+  GNULIB_FUTIMENS=0;  AC_SUBST([GNULIB_FUTIMENS])
   GNULIB_LCHMOD=0;    AC_SUBST([GNULIB_LCHMOD])
   GNULIB_LSTAT=0;     AC_SUBST([GNULIB_LSTAT])
   GNULIB_MKDIRAT=0;   AC_SUBST([GNULIB_MKDIRAT])
@@ -50,6 +51,7 @@
   dnl Assume proper GNU behavior unless another module says otherwise.
   HAVE_FCHMODAT=1;    AC_SUBST([HAVE_FCHMODAT])
   HAVE_FSTATAT=1;     AC_SUBST([HAVE_FSTATAT])
+  HAVE_FUTIMENS=1;    AC_SUBST([HAVE_FUTIMENS])
   HAVE_LCHMOD=1;      AC_SUBST([HAVE_LCHMOD])
   HAVE_LSTAT=1;       AC_SUBST([HAVE_LSTAT])
   HAVE_MKDIRAT=1;     AC_SUBST([HAVE_MKDIRAT])
@@ -57,6 +59,7 @@
   HAVE_MKNODAT=1;     AC_SUBST([HAVE_MKNODAT])
   REPLACE_FSTAT=0;    AC_SUBST([REPLACE_FSTAT])
   REPLACE_FSTATAT=0;  AC_SUBST([REPLACE_FSTATAT])
+  REPLACE_FUTIMENS=0; AC_SUBST([REPLACE_FUTIMENS])
   REPLACE_LSTAT=0;    AC_SUBST([REPLACE_LSTAT])
   REPLACE_MKDIR=0;    AC_SUBST([REPLACE_MKDIR])
   REPLACE_STAT=0;     AC_SUBST([REPLACE_STAT])

new file mode 100644
--- /dev/null
+++ b/modules/futimens
@@ -0,0 +1,28 @@
+Description:
+Set file access and modification times of a file descriptor.
+
+Files:
+lib/futimens.c
+m4/futimens.m4
+
+Depends-on:
+sys_stat
+utimens
+
+configure.ac:
+gl_FUNC_FUTIMENS
+gl_SYS_STAT_MODULE_INDICATOR([futimens])
+
+Makefile.am:
+
+Include:
+<sys/stat.h>
+
+Link:
+$(LIB_CLOCK_GETTIME)
+
+License:
+GPL
+
+Maintainer:
+Eric Blake

new file mode 100644
--- /dev/null
+++ b/modules/futimens-tests
@@ -0,0 +1,15 @@
+Files:
+tests/test-futimens.h
+tests/test-futimens.c
+
+Depends-on:
+timespec
+utimecmp
+
+configure.ac:
+AC_CHECK_FUNCS_ONCE([usleep])
+
+Makefile.am:
+TESTS += test-futimens
+check_PROGRAMS += test-futimens
+test_futimens_LDADD = $(LDADD) $(LIB_CLOCK_GETTIME) @LIBINTL@

--- a/modules/sys_stat
+++ b/modules/sys_stat
@@ -28,6 +28,7 @@
 	      -e 's|@''NEXT_SYS_STAT_H''@|$(NEXT_SYS_STAT_H)|g' \
 	      -e 's|@''GNULIB_FCHMODAT''@|$(GNULIB_FCHMODAT)|g' \
 	      -e 's|@''GNULIB_FSTATAT''@|$(GNULIB_FSTATAT)|g' \
+	      -e 's|@''GNULIB_FUTIMENS''@|$(GNULIB_FUTIMENS)|g' \
 	      -e 's|@''GNULIB_LCHMOD''@|$(GNULIB_LCHMOD)|g' \
 	      -e 's|@''GNULIB_LSTAT''@|$(GNULIB_LSTAT)|g' \
 	      -e 's|@''GNULIB_MKDIRAT''@|$(GNULIB_MKDIRAT)|g' \
@@ -36,6 +37,7 @@
 	      -e 's|@''GNULIB_STAT''@|$(GNULIB_STAT)|g' \
 	      -e 's|@''HAVE_FCHMODAT''@|$(HAVE_FCHMODAT)|g' \
 	      -e 's|@''HAVE_FSTATAT''@|$(HAVE_FSTATAT)|g' \
+	      -e 's|@''HAVE_FUTIMENS''@|$(HAVE_FUTIMENS)|g' \
 	      -e 's|@''HAVE_LCHMOD''@|$(HAVE_LCHMOD)|g' \
 	      -e 's|@''HAVE_LSTAT''@|$(HAVE_LSTAT)|g' \
 	      -e 's|@''HAVE_MKDIRAT''@|$(HAVE_MKDIRAT)|g' \
@@ -43,6 +45,7 @@
 	      -e 's|@''HAVE_MKNODAT''@|$(HAVE_MKNODAT)|g' \
 	      -e 's|@''REPLACE_FSTAT''@|$(REPLACE_FSTAT)|g' \
 	      -e 's|@''REPLACE_FSTATAT''@|$(REPLACE_FSTATAT)|g' \
+	      -e 's|@''REPLACE_FUTIMENS''@|$(REPLACE_FUTIMENS)|g' \
 	      -e 's|@''REPLACE_LSTAT''@|$(REPLACE_LSTAT)|g' \
 	      -e 's|@''REPLACE_MKDIR''@|$(REPLACE_MKDIR)|g' \
 	      -e 's|@''REPLACE_STAT''@|$(REPLACE_STAT)|g' \

new file mode 100644
--- /dev/null
+++ b/tests/test-futimens.c
@@ -0,0 +1,58 @@
+/* Tests of futimens.
+   Copyright (C) 2009 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* Written by Eric Blake <ebb9@byu.net>, 2009.  */
+
+#include <config.h>
+
+#include <sys/stat.h>
+
+#include <fcntl.h>
+#include <errno.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "stat-time.h"
+#include "timespec.h"
+#include "utimecmp.h"
+
+#define ASSERT(expr) \
+  do                                                                         \
+    {                                                                        \
+      if (!(expr))                                                           \
+        {                                                                    \
+          fprintf (stderr, "%s:%d: assertion failed\n", __FILE__, __LINE__);  \
+          fflush (stderr);                                                   \
+          abort ();                                                          \
+        }                                                                    \
+    }                                                                        \
+  while (0)
+
+#define BASE "test-futimens.t"
+
+#include "test-futimens.h"
+
+int
+main ()
+{
+  /* Clean up any trash from prior testsuite runs.  */
+  ASSERT (system ("rm -rf " BASE "*") == 0);
+
+  return test_futimens (futimens, true);
+}