--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,14 @@
+2007-05-01  Bruno Haible  <bruno@clisp.org>
+
+	* modules/sleep: New file.
+	* lib/sleep.c: New file.
+	* m4/sleep.m4: New file.
+	* lib/unistd_.h (sleep): New declaration.
+	* m4/unistd_h.m4 (gl_UNISTD_H_DEFAULTS): Initialize GNULIB_SLEEP,
+	HAVE_SLEEP.
+	* modules/unistd (Makefile.am): Substitute GNULIB_SLEEP, HAVE_SLEEP.
+	* doc/functions/sleep.texi: Document the sleep module.
+
 2007-05-01  Bruno Haible  <bruno@clisp.org>
 
 	* lib/sigprocmask.h: Remove file.

--- a/doc/functions/sleep.texi
+++ b/doc/functions/sleep.texi
@@ -4,10 +4,13 @@
 
 POSIX specification: @url{http://www.opengroup.org/susv3xsh/sleep.html}
 
-Gnulib module: ---
+Gnulib module: sleep
 
 Portability problems fixed by Gnulib:
 @itemize
+@item
+This function is missing on some platforms:
+mingw (2005 or newer).
 @end itemize
 
 Portability problems not fixed by Gnulib:

new file mode 100644
--- /dev/null
+++ b/lib/sleep.c
@@ -0,0 +1,47 @@
+/* Pausing execution of the current thread.
+   Copyright (C) 2007 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2007.
+
+   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 2, 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, write to the Free Software Foundation,
+   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include <unistd.h>
+
+#if (defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__
+
+# define WIN32_LEAN_AND_MEAN  /* avoid including junk */
+# include <windows.h>
+
+unsigned int
+sleep (unsigned int seconds)
+{
+  unsigned int remaining;
+
+  /* Sleep for 1 second many times, because
+       1. Sleep is not interruptiple by Ctrl-C,
+       2. we want to avoid arithmetic overflow while multiplying with 1000.  */
+  for (remaining = seconds; remaining > 0; remaining--)
+    Sleep (1000);
+
+  return remaining;
+}
+
+#else
+
+ #error "Please port gnulib sleep.c to your platform, possibly using usleep() or select(), then report this to bug-gnulib."
+
+#endif

--- a/lib/unistd_.h
+++ b/lib/unistd_.h
@@ -191,6 +191,23 @@
 #endif
 
 
+#if @GNULIB_SLEEP@
+/* Pause the execution of the current thread for N seconds.
+   Returns the number of seconds left to sleep.
+   See the POSIX:2001 specification
+   <http://www.opengroup.org/susv3xsh/sleep.html>.  */
+# if !@HAVE_SLEEP@
+extern unsigned int sleep (unsigned int n);
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef sleep
+# define sleep(n) \
+    (GL_LINK_WARNING ("sleep is unportable - " \
+                      "use gnulib module sleep for portability"), \
+     sleep (n))
+#endif
+
+
 #ifdef __cplusplus
 }
 #endif

new file mode 100644
--- /dev/null
+++ b/m4/sleep.m4
@@ -0,0 +1,19 @@
+# sleep.m4 serial 1
+dnl Copyright (C) 2007 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.
+
+AC_DEFUN([gl_FUNC_SLEEP],
+[
+  AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+  AC_CHECK_FUNCS_ONCE([sleep])
+  if test $ac_cv_func_sleep = no; then
+    HAVE_SLEEP=0
+    AC_LIBOBJ([sleep])
+    gl_PREREQ_SLEEP
+  fi
+])
+
+# Prerequisites of lib/sleep.c.
+AC_DEFUN([gl_PREREQ_SLEEP], [:])

--- a/m4/unistd_h.m4
+++ b/m4/unistd_h.m4
@@ -1,4 +1,4 @@
-# unistd_h.m4 serial 5
+# unistd_h.m4 serial 6
 dnl Copyright (C) 2006-2007 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -40,10 +40,12 @@
   GNULIB_GETCWD=0;        AC_SUBST([GNULIB_GETCWD])
   GNULIB_GETLOGIN_R=0;    AC_SUBST([GNULIB_GETLOGIN_R])
   GNULIB_READLINK=0;      AC_SUBST([GNULIB_READLINK])
+  GNULIB_SLEEP=0;         AC_SUBST([GNULIB_SLEEP])
   dnl Assume proper GNU behavior unless another module says otherwise.
   HAVE_DUP2=1;            AC_SUBST([HAVE_DUP2])
   HAVE_FTRUNCATE=1;       AC_SUBST([HAVE_FTRUNCATE])
   HAVE_READLINK=1;        AC_SUBST([HAVE_READLINK])
+  HAVE_SLEEP=1;           AC_SUBST([HAVE_SLEEP])
   HAVE_DECL_GETLOGIN_R=1; AC_SUBST([HAVE_DECL_GETLOGIN_R])
   REPLACE_CHOWN=0;        AC_SUBST([REPLACE_CHOWN])
   REPLACE_FCHDIR=0;       AC_SUBST([REPLACE_FCHDIR])

new file mode 100644
--- /dev/null
+++ b/modules/sleep
@@ -0,0 +1,25 @@
+Description:
+sleep() function: pause execution of the current thread.
+
+Files:
+lib/sleep.c
+m4/sleep.m4
+
+Depends-on:
+unistd
+
+configure.ac:
+gl_FUNC_SLEEP
+gl_UNISTD_MODULE_INDICATOR([sleep])
+
+Makefile.am:
+
+Include:
+<unistd.h>
+
+License:
+LGPL
+
+Maintainer:
+Bruno Haible
+

--- a/modules/unistd
+++ b/modules/unistd
@@ -29,9 +29,11 @@
 	      -e 's|@''GNULIB_GETCWD''@|$(GNULIB_GETCWD)|g' \
 	      -e 's|@''GNULIB_GETLOGIN_R''@|$(GNULIB_GETLOGIN_R)|g' \
 	      -e 's|@''GNULIB_READLINK''@|$(GNULIB_READLINK)|g' \
+	      -e 's|@''GNULIB_SLEEP''@|$(GNULIB_SLEEP)|g' \
 	      -e 's|@''HAVE_DUP2''@|$(HAVE_DUP2)|g' \
 	      -e 's|@''HAVE_FTRUNCATE''@|$(HAVE_FTRUNCATE)|g' \
 	      -e 's|@''HAVE_READLINK''@|$(HAVE_READLINK)|g' \
+	      -e 's|@''HAVE_SLEEP''@|$(HAVE_SLEEP)|g' \
 	      -e 's|@''HAVE_DECL_GETLOGIN_R''@|$(HAVE_DECL_GETLOGIN_R)|g' \
 	      -e 's|@''REPLACE_CHOWN''@|$(REPLACE_CHOWN)|g' \
 	      -e 's|@''REPLACE_FCHDIR''@|$(REPLACE_FCHDIR)|g' \