2 dnl Copyright (C) 2007-2011 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
7 AC_DEFUN([gl_FUNC_FSEEKO],
9 AC_REQUIRE([gl_STDIO_H_DEFAULTS])
10 AC_REQUIRE([gl_HAVE_FSEEKO])
11 AC_REQUIRE([gl_STDIN_LARGE_OFFSET])
13 AC_CHECK_DECLS_ONCE([fseeko])
14 if test $ac_cv_have_decl_fseeko = no; then
18 if test $gl_cv_func_fseeko = no; then
21 if test $gl_cv_var_stdin_large_offset = no; then
24 m4_ifdef([gl_FUNC_FFLUSH_STDIN], [
26 if test $gl_cv_func_fflush_stdin = no; then
31 if test $HAVE_FSEEKO = 0 || test $REPLACE_FSEEKO = 1; then
32 dnl If we are also using the fseek module, then fseek needs replacing, too.
33 m4_ifdef([gl_REPLACE_FSEEK], [gl_REPLACE_FSEEK])
37 dnl Tests whether fseeko is available.
38 dnl Result is gl_cv_func_fseeko.
39 AC_DEFUN([gl_HAVE_FSEEKO],
41 AC_REQUIRE([AC_PROG_CC])
43 dnl Persuade glibc <stdio.h> to declare fseeko().
44 AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
46 AC_CACHE_CHECK([for fseeko], [gl_cv_func_fseeko],
48 AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <stdio.h>
49 ]], [fseeko (stdin, 0, 0);])],
50 [gl_cv_func_fseeko=yes], [gl_cv_func_fseeko=no])
54 dnl Code shared by fseeko and ftello. Determine if large files are supported,
55 dnl but stdin does not start as a large file by default.
56 AC_DEFUN([gl_STDIN_LARGE_OFFSET],
58 AC_CACHE_CHECK([whether stdin defaults to large file offsets],
59 [gl_cv_var_stdin_large_offset],
60 [AC_LINK_IFELSE([AC_LANG_PROGRAM([[#include <stdio.h>]],
61 [[#if defined __SL64 && defined __SCLE /* cygwin */
62 /* Cygwin 1.5.24 and earlier fail to put stdin in 64-bit mode, making
63 fseeko/ftello needlessly fail. This bug was fixed in 1.5.25, and
64 it is easier to do a version check than building a runtime test. */
65 # include <cygwin/version.h>
66 # if CYGWIN_VERSION_DLL_COMBINED < CYGWIN_VERSION_DLL_MAKE_COMBINED (1005, 25)
70 [gl_cv_var_stdin_large_offset=yes],
71 [gl_cv_var_stdin_large_offset=no])])