1# double-slash-root.m4 serial 4 -*- Autoconf -*- 2dnl Copyright (C) 2006, 2008-2012 Free Software Foundation, Inc. 3dnl This file is free software; the Free Software Foundation 4dnl gives unlimited permission to copy and/or distribute it, 5dnl with or without modifications, as long as this notice is preserved. 6 7AC_DEFUN([gl_DOUBLE_SLASH_ROOT], 8[ 9 AC_REQUIRE([AC_CANONICAL_HOST]) 10 AC_CACHE_CHECK([whether // is distinct from /], [gl_cv_double_slash_root], 11 [ if test x"$cross_compiling" = xyes ; then 12 # When cross-compiling, there is no way to tell whether // is special 13 # short of a list of hosts. However, the only known hosts to date 14 # that have a distinct // are Apollo DomainOS (too old to port to), 15 # Cygwin, and z/OS. If anyone knows of another system for which // has 16 # special semantics and is distinct from /, please report it to 17 # <bug-gnulib@gnu.org>. 18 case $host in 19 *-cygwin | i370-ibm-openedition) 20 gl_cv_double_slash_root=yes ;; 21 *) 22 # Be optimistic and assume that / and // are the same when we 23 # don't know. 24 gl_cv_double_slash_root='unknown, assuming no' ;; 25 esac 26 else 27 set x `ls -di / // 2>/dev/null` 28 if test "$[2]" = "$[4]" && wc //dev/null >/dev/null 2>&1; then 29 gl_cv_double_slash_root=no 30 else 31 gl_cv_double_slash_root=yes 32 fi 33 fi]) 34 if test "$gl_cv_double_slash_root" = yes; then 35 AC_DEFINE([DOUBLE_SLASH_IS_DISTINCT_ROOT], [1], 36 [Define to 1 if // is a file system root distinct from /.]) 37 fi 38]) 39