1# serial 7 2 3# Copyright (C) 2005-2007, 2009-2021 Free Software Foundation, Inc. 4# 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. 8 9# Written by Paul Eggert. 10 11AC_DEFUN([gl_UNLINKDIR], 12[ 13 AC_REQUIRE([AC_CANONICAL_HOST]) 14 AC_CHECK_HEADERS_ONCE([priv.h]) 15 16 # The Hurd, the Linux kernel, the FreeBSD kernel version 2.2 and later, 17 # Cygwin, and mingw never let anyone (even root) unlink directories. 18 # If anyone knows of another system for which unlink can never 19 # remove a directory, please report it to <bug-coreutils@gnu.org>. 20 # Unfortunately this is difficult to test for, since it requires root access 21 # and might create garbage in the file system, 22 # so the code below simply relies on the kernel name and version number. 23 case $host_os in 24 gnu[[0-9]]* | \ 25 linux-* | linux | \ 26 freebsd2.2* | freebsd[[3-9]]* | freebsd[[1-9]][[0-9]]* | \ 27 cygwin | \ 28 mingw*) 29 AC_DEFINE([UNLINK_CANNOT_UNLINK_DIR], [1], 30 [Define to 1 if unlink (dir) cannot possibly succeed.]);; 31 esac 32]) 33