--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,16 @@
+2011-09-21  Bruno Haible  <bruno@clisp.org>
+
+	ftruncate: Un-deprecate, concentrate on Win32 support.
+	* modules/ftruncate (Status, Notice): Remove sections.
+	(Depends-on): Add largefile.
+	* m4/ftruncate.m4 (gl_FUNC_FTRUNCATE): Drop failure message on
+	non-mingw platforms.
+	* lib/ftruncate.c: Remove code for the older platforms. For Win32,
+	include <io.h>.
+	* modules/perror-tests (Depends-on): Add ftruncate.
+	* doc/posix-functions/ftruncate.texi: Mention the MSVC problem and the
+	'ftruncate' module.
+
 2011-09-21  Bruno Haible  <bruno@clisp.org>
 
 	Add dependencies to new dirent related modules.

--- a/doc/posix-functions/ftruncate.texi
+++ b/doc/posix-functions/ftruncate.texi
@@ -4,16 +4,19 @@
 
 POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/ftruncate.html}
 
-Gnulib module: ---
+Gnulib module: ftruncate
 
 Portability problems fixed by Gnulib:
 @itemize
-@end itemize
-
-Portability problems not fixed by Gnulib:
-@itemize
+@item
+This function is missing on some platforms:
+MSVC 9.
 @item
 On platforms where @code{off_t} is a 32-bit type, this function is not
 applicable to arbitrary lengths for files larger than 2 GB.  The fix is to
 use the @code{AC_SYS_LARGEFILE} macro.
 @end itemize
+
+Portability problems not fixed by Gnulib:
+@itemize
+@end itemize

--- a/lib/ftruncate.c
+++ b/lib/ftruncate.c
@@ -1,4 +1,4 @@
-/* ftruncate emulations that work on some System V's.
+/* ftruncate emulations for native Windows.
    This file is in the public domain.  */
 
 #include <config.h>
@@ -6,67 +6,9 @@
 /* Specification.  */
 #include <unistd.h>
 
-#include <sys/types.h>
-#include <fcntl.h>
-
-#ifdef F_CHSIZE
-
-int
-ftruncate (int fd, off_t length)
-{
-  return fcntl (fd, F_CHSIZE, length);
-}
-
-#else /* not F_CHSIZE */
-# ifdef F_FREESP
-
-/* By William Kucharski <kucharsk@netcom.com>.  */
-
-#  include <sys/stat.h>
-#  include <errno.h>
-
-int
-ftruncate (int fd, off_t length)
-{
-  struct flock fl;
-  struct stat filebuf;
-
-  if (fstat (fd, &filebuf) < 0)
-    return -1;
+#if HAVE_CHSIZE
 
-  if (filebuf.st_size < length)
-    {
-      /* Extend file length. */
-      if (lseek (fd, (length - 1), SEEK_SET) < 0)
-        return -1;
-
-      /* Write a "0" byte. */
-      if (write (fd, "", 1) != 1)
-        return -1;
-    }
-  else
-    {
-
-      /* Truncate length. */
-
-      fl.l_whence = 0;
-      fl.l_len = 0;
-      fl.l_start = length;
-      fl.l_type = F_WRLCK;      /* write lock on file space */
-
-      /* This relies on the *undocumented* F_FREESP argument to fcntl,
-         which truncates the file so that it ends at the position
-         indicated by fl.l_start.  Will minor miracles never cease?  */
-
-      if (fcntl (fd, F_FREESP, &fl) < 0)
-        return -1;
-    }
-
-  return 0;
-}
-
-# else /* not F_CHSIZE nor F_FREESP */
-#  if HAVE_CHSIZE                      /* native Windows, e.g. mingw */
+# include <io.h>
 
 int
 ftruncate (int fd, off_t length)
@@ -74,17 +16,4 @@
   return chsize (fd, length);
 }
 
-#  else /* not F_CHSIZE nor F_FREESP nor HAVE_CHSIZE */
-
-#   include <errno.h>
-
-int
-ftruncate (int fd, off_t length)
-{
-  errno = EIO;
-  return -1;
-}
-
-#  endif /* not HAVE_CHSIZE */
-# endif /* not F_FREESP */
-#endif /* not F_CHSIZE */
+#endif

--- a/m4/ftruncate.m4
+++ b/m4/ftruncate.m4
@@ -1,41 +1,18 @@
-# serial 16
+# serial 17
 
-# See if we need to emulate a missing ftruncate function using fcntl or chsize.
+# See if we need to emulate a missing ftruncate function using chsize.
 
 # Copyright (C) 2000-2001, 2003-2007, 2009-2011 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
 # gives unlimited permission to copy and/or distribute it,
 # with or without modifications, as long as this notice is preserved.
 
-# FIXME: remove this macro, along with all uses of HAVE_FTRUNCATE in 2012,
-# if the check below provokes no more reports.  So far, the only report
-# arose from a test build of this gnulib module, cross-compiling to mingw:
-# <http://thread.gmane.org/gmane.comp.lib.gnulib.bugs/9203>
-# Now (in 2010), MSVC has been raised as a possible target:
-# <http://thread.gmane.org/gmane.comp.lib.gnulib.bugs/21394/focus=21396>
-
 AC_DEFUN([gl_FUNC_FTRUNCATE],
 [
   AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
-  AC_REQUIRE([AC_CANONICAL_HOST])
   AC_CHECK_FUNCS_ONCE([ftruncate])
   if test $ac_cv_func_ftruncate = no; then
     HAVE_FTRUNCATE=0
-    case "$host_os" in
-      mingw*)
-        # Yes, we know mingw lacks ftruncate.
-        ;;
-      *)
-        # If someone lacks ftruncate, make configure fail, and request
-        # a bug report to inform us about it.
-        if test x"$SKIP_FTRUNCATE_CHECK" != xyes; then
-          AC_MSG_FAILURE([Your system lacks the ftruncate function.
-              Please report this, along with the output of "uname -a", to the
-              bug-coreutils@gnu.org mailing list.  To continue past this point,
-              rerun configure with SKIP_FTRUNCATE_CHECK=yes.
-              E.g., ./configure SKIP_FTRUNCATE_CHECK=yes])
-        fi
-    esac
   fi
 ])
 

--- a/modules/ftruncate
+++ b/modules/ftruncate
@@ -1,18 +1,13 @@
 Description:
 ftruncate() function: truncate an open file to a specified length.
 
-Status:
-obsolete
-
-Notice:
-This module is obsolete.
-
 Files:
 lib/ftruncate.c
 m4/ftruncate.m4
 
 Depends-on:
 unistd
+largefile
 
 configure.ac:
 gl_FUNC_FTRUNCATE

--- a/modules/perror-tests
+++ b/modules/perror-tests
@@ -8,6 +8,7 @@
 
 Depends-on:
 dup2
+ftruncate
 strerror
 
 configure.ac: