Update.

2003-03-02  Ulrich Drepper  <drepper@redhat.com>

	* sysdeps/unix/sysv/linux/bits/posix_opt.h: Define
	_POSIX_MONOTONIC_CLOCK.
	* linuxthreads/sysdeps/unix/sysv/linux/i386/bits/posix_opt.h: Likewise.

sysdeps/unix/sysv/linux/clock_nanosleep.c

@@ -0,0 +1,65 @@
+/* Copyright (C) 2003 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <time.h>
+
+#include <sysdep.h>
+#include "kernel-features.h"
+
+
+#ifdef __ASSUME_POSIX_TIMERS
+/* We can simply use the syscall.  The CPU clocks are not supported
+   with this function.  */
+int
+clock_nanosleep (clockid_t clock_id, int flags, const struct timespec *req,
+		 struct timespec *rem)
+{
+  INTERNAL_SYSCALL_DECL (err);
+  int r;
+
+  r = INTERNAL_SYSCALL (clock_nanosleep, err, 4, clock_id, flags, req, rem);
+  return (INTERNAL_SYSCALL_ERROR_P (r, err)
+	  ? INTERNAL_SYSCALL_ERRNO (r, err) : 0);
+}
+
+#else
+# ifdef __NR_clock_nanosleep
+/* Is the syscall known to exist?  */
+extern int __libc_missing_posix_timers attribute_hidden;
+
+/* The REALTIME and MONOTONIC clock might be available.  Try the
+   syscall first.  */
+#  define SYSDEP_NANOSLEEP \
+  if (!__libc_missing_posix_timers)					      \
+    {									      \
+      INTERNAL_SYSCALL_DECL (err);					      \
+      int r = INTERNAL_SYSCALL (clock_nanosleep, err, 4, clock_id, flags,     \
+				req, rem);				      \
+									      \
+      if (!INTERNAL_SYSCALL_ERROR_P (r, err))				      \
+	return 0;							      \
+									      \
+      if (INTERNAL_SYSCALL_ERRNO (r, err) != ENOSYS)			      \
+	return INTERNAL_SYSCALL_ERRNO (r, err);				      \
+      									      \
+      __libc_missing_posix_timers = 1;					      \
+    }
+# endif
+
+# include <sysdeps/unix/clock_nanosleep.c>
+#endif