3 # Copyright (C) 2005, 2006, 2007 Free Software Foundation, Inc.
5 # This file is free software; the Free Software Foundation
6 # gives unlimited permission to copy and/or distribute it,
7 # with or without modifications, as long as this notice is preserved.
9 # Written by Paul Eggert.
11 AC_DEFUN([gl_UNLINKDIR],
13 AC_REQUIRE([AC_CANONICAL_HOST])
14 AC_CHECK_HEADERS_ONCE(priv.h)
16 AC_LIBOBJ([unlinkdir])
18 # The Hurd, the Linux kernel, the FreeBSD kernel version 2.2 and later,
19 # and Cygwin never let anyone (even root) unlink directories.
20 # If anyone knows of another system for which unlink can never
21 # remove a directory, please report it to <bug-coreutils@gnu.org>.
22 # Unfortunately this is difficult to test for, since it requires root access
23 # and might create garbage in the file system,
24 # so the code below simply relies on the kernel name and version number.
27 *-*-linux-* | *-*-linux | \
28 *-*-freebsd2.2* | *-*-freebsd[[3-9]]* | *-*-freebsd[[1-9]][[0-9]]* | \
30 AC_DEFINE([UNLINK_CANNOT_UNLINK_DIR], 1,
31 [Define to 1 if unlink (dir) cannot possibly succeed.]);;