--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,15 @@
 2011-05-02  Eric Blake  <eblake@redhat.com>
 
+	fflush: also replace fclose when fixing fflush
+	* modules/fflush (Depends-on): Add fclose.
+	* m4/fflush.m4 (gl_FUNC_FFLUSH): Also replace fclose.
+	* lib/fclose.c (rpl_fclose): Don't cause spurious failures on
+	memstreams with no backing fd.
+	* doc/posix-functions/fclose.texi (fclose): Document the use of
+	fflush module to fix the bug.
+	* tests/test-fclose.c (main): Relax test when fclose is used in
+	isolation.
+
 	fclose: add some tests
 	* modules/fclose-tests: New test module.
 	* tests/test-fclose.c: New file.

--- a/doc/posix-functions/fclose.texi
+++ b/doc/posix-functions/fclose.texi
@@ -4,9 +4,17 @@
 
 POSIX specification:@* @url{http://www.opengroup.org/onlinepubs/9699919799/functions/fclose.html}
 
-Gnulib module: fclose
+Gnulib module: fclose, fflush
 
-Portability problems fixed by Gnulib:
+Portability problems fixed by Gnulib module @code{fflush}:
+@itemize
+@item
+On some platforms, this function fails to set the file position of a
+seekable input stream to the byte after the last one actually read:
+glibc 2.13, FreeBSD.
+@end itemize
+
+Portability problems fixed by Gnulib module @code{fclose}:
 @itemize
 @item
 On Windows platforms (excluding Cygwin), @code{socket} and @code{accept}
@@ -17,10 +25,6 @@
 Portability problems not fixed by Gnulib:
 @itemize
 @item
-On some platforms, this function fails to set the file position of a
-seekable input stream to the byte after the last one actually read:
-glibc 2.13, FreeBSD.
-@item
 On Windows platforms (excluding Cygwin), this function does not set @code{errno}
 upon failure.
 @end itemize

--- a/lib/fclose.c
+++ b/lib/fclose.c
@@ -24,13 +24,19 @@
 
 #include "freading.h"
 
-/* Override fclose() to call the overridden close().  */
+/* Override fclose() to call the overridden fflush() or close().  */
 
 int
 rpl_fclose (FILE *fp)
 #undef fclose
 {
   int saved_errno = 0;
+  int fd;
+
+  /* Don't change behavior on memstreams.  */
+  fd = fileno (fp);
+  if (fd < 0)
+    return fclose (fp);
 
   /* We only need to flush the file if it is not reading or if it is
      seekable.  This only guarantees the file position of input files
@@ -39,7 +45,7 @@
       && fflush (fp))
     saved_errno = errno;
 
-  if (close (fileno (fp)) < 0 && saved_errno == 0)
+  if (close (fd) < 0 && saved_errno == 0)
     saved_errno = errno;
 
   fclose (fp); /* will fail with errno = EBADF */

--- a/m4/fflush.m4
+++ b/m4/fflush.m4
@@ -1,4 +1,4 @@
-# fflush.m4 serial 8
+# fflush.m4 serial 9
 
 # Copyright (C) 2007-2011 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -61,6 +61,7 @@
     ])
   if test $gl_cv_func_fflush_stdin = no; then
     gl_REPLACE_FFLUSH
+    gl_REPLACE_FCLOSE
   fi
 ])
 

--- a/modules/fflush
+++ b/modules/fflush
@@ -7,6 +7,7 @@
 m4/fflush.m4
 
 Depends-on:
+fclose
 fpurge
 ftello
 freading
@@ -20,6 +21,7 @@
 
 configure.ac:
 gl_FUNC_FFLUSH
+gl_MODULE_INDICATOR([fflush])
 gl_STDIO_MODULE_INDICATOR([fflush])
 
 Makefile.am:

--- a/tests/test-fclose.c
+++ b/tests/test-fclose.c
@@ -62,7 +62,9 @@
   ASSERT (errno == EBADF);
   ASSERT (lseek (fd, 0, SEEK_CUR) == 2);
 
-  /* Likewise for an input stream.  */
+#if GNULIB_FFLUSH
+  /* Likewise for an input stream, but only when we know fflush works
+     on input streams.  */
   fd2 = dup (fd);
   ASSERT (0 <= fd2);
   f = fdopen (fd2, "r");
@@ -73,6 +75,7 @@
   ASSERT (lseek (fd2, 0, SEEK_CUR) == -1);
   ASSERT (errno == EBADF);
   ASSERT (lseek (fd, 0, SEEK_CUR) == 3);
+#endif
 
   /* Test that fclose() sets errno if someone else closes the stream
      fd behind the back of stdio.  */