2 dnl Copyright (C) 2006-2010 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_FCHDIR],
9 AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
10 AC_REQUIRE([gl_DIRENT_H_DEFAULTS])
11 AC_REQUIRE([gl_SYS_STAT_H_DEFAULTS])
12 AC_CHECK_FUNCS_ONCE([fchdir])
13 if test $ac_cv_func_fchdir = no; then
17 AC_DEFINE([REPLACE_FCHDIR], [1],
18 [Define to 1 if gnulib's fchdir() replacement is used.])
19 dnl We must also replace anything that can manipulate a directory fd,
20 dnl to keep our bookkeeping up-to-date. We don't have to replace
21 dnl fstatat, since no platform has fstatat but lacks fchdir.
28 dnl dup3 is already unconditionally replaced
31 AC_CACHE_CHECK([whether open can visit directories],
32 [gl_cv_func_open_directory_works],
33 [AC_RUN_IFELSE([AC_LANG_PROGRAM([[#include <fcntl.h>
34 ]], [return open(".", O_RDONLY) < 0;])],
35 [gl_cv_func_open_directory_works=yes],
36 [gl_cv_func_open_directory_works=no],
37 [gl_cv_func_open_directory_works="guessing no"])])
38 if test "$gl_cv_func_open_directory_works" != yes; then
39 AC_DEFINE([REPLACE_OPEN_DIRECTORY], [1], [Define to 1 if open() should
40 work around the inability to open a directory.])
46 # Prerequisites of lib/fchdir.c.
47 AC_DEFUN([gl_PREREQ_FCHDIR], [:])