fseeko: missing declaration on glibc systems

[Bruno Haible]

Testing the 'fflush' module on a Linux/x86 systems, I got this warning:

test-fflush.c: Dans la fonction « main »:
test-fflush.c:103: Warnung: implicit declaration of function `fseeko'

This fixes it. Committed.


2008-03-06  Bruno Haible  <address@hidden>

        * modules/fseeko (Dependencies): Add extensions.
        * m4/fseeko.m4 (gl_FUNC_FSEEKO): Require AC_USE_SYSTEM_EXTENSIONS.
        Needed on glibc systems.

*** modules/fseeko.orig 2008-03-06 23:16:50.000000000 +0100
--- modules/fseeko      2008-03-06 23:14:55.000000000 +0100
***************
*** 6,11 ****
--- 6,12 ----
  m4/fseeko.m4
  
  Depends-on:
+ extensions
  lseek
  stdio
  
*** m4/fseeko.m4.orig   2008-03-06 23:16:50.000000000 +0100
--- m4/fseeko.m4        2008-03-06 23:14:30.000000000 +0100
***************
*** 1,5 ****
! # fseeko.m4 serial 3
! 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.
--- 1,5 ----
! # fseeko.m4 serial 4
! dnl Copyright (C) 2007-2008 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.
***************
*** 9,14 ****
--- 9,18 ----
    AC_REQUIRE([gl_STDIO_H_DEFAULTS])
    AC_REQUIRE([AC_PROG_CC])
    AC_REQUIRE([gl_STDIN_LARGE_OFFSET])
+ 
+   dnl Persuade glibc <stdio.h> to declare fseeko().
+   AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
+ 
    AC_CACHE_CHECK([for fseeko], [gl_cv_func_fseeko],
      [
        AC_TRY_LINK([#include <stdio.h>], [fseeko (stdin, 0, 0);],