maint: update all copyright year number ranges

[gnulib.git] / m4 / double-slash-root.m4

diff --git a/m4/double-slash-root.m4 b/m4/double-slash-root.m4
index f8cbd54..bd6f867 100644 (file)
--- a/m4/double-slash-root.m4
+++ b/m4/double-slash-root.m4
@@ -1,5 +1,5 @@
-#serial 1   -*- autoconf -*-
-dnl Copyright (C) 2006 Free Software Foundation, Inc.
+# double-slash-root.m4 serial 4   -*- Autoconf -*-
+dnl Copyright (C) 2006, 2008-2013 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
@@ -7,37 +7,32 @@ dnl with or without modifications, as long as this notice is preserved.
 AC_DEFUN([gl_DOUBLE_SLASH_ROOT],
 [
   AC_REQUIRE([AC_CANONICAL_HOST])
-  AC_CACHE_CHECK([whether // is distinct from /], [ac_cv_double_slash_root],
+  AC_CACHE_CHECK([whether // is distinct from /], [gl_cv_double_slash_root],
     [ if test x"$cross_compiling" = xyes ; then
-       # When cross-compiling, there is no way to tell whether // is special
-       # short of a list of hosts.  However, the only known hosts to date
-       # that have a distinct // are Apollo DomainOS (too old to port to)
-       # and Cygwin.  If anyone knows of another system for which // has
-       # special semantics and is distinct from /, please report it to
-       # <bug-coreutils@gnu.org>.
-       case $host in
-         *-cygwin)
-           ac_cv_double_slash_root=yes ;;
-         *)
-           # Be optimistic and assume that / and // are the same when we
-           # don't know.
-           ac_cv_double_slash_root='unknown, assuming no' ;;
-       esac
+        # When cross-compiling, there is no way to tell whether // is special
+        # short of a list of hosts.  However, the only known hosts to date
+        # that have a distinct // are Apollo DomainOS (too old to port to),
+        # Cygwin, and z/OS.  If anyone knows of another system for which // has
+        # special semantics and is distinct from /, please report it to
+        # <bug-gnulib@gnu.org>.
+        case $host in
+          *-cygwin | i370-ibm-openedition)
+            gl_cv_double_slash_root=yes ;;
+          *)
+            # Be optimistic and assume that / and // are the same when we
+            # don't know.
+            gl_cv_double_slash_root='unknown, assuming no' ;;
+        esac
       else
-       set x `ls -di / //`
-       if test $[2] = $[4]; then
-         ac_cv_double_slash_root=no
-       else
-         ac_cv_double_slash_root=yes
-       fi
+        set x `ls -di / // 2>/dev/null`
+        if test "$[2]" = "$[4]" && wc //dev/null >/dev/null 2>&1; then
+          gl_cv_double_slash_root=no
+        else
+          gl_cv_double_slash_root=yes
+        fi
       fi])
-  if test x"$ac_cv_double_slash_root" = xyes; then
-    ac_double_slash_root=1
-  else
-    ac_double_slash_root=0
+  if test "$gl_cv_double_slash_root" = yes; then
+    AC_DEFINE([DOUBLE_SLASH_IS_DISTINCT_ROOT], [1],
+      [Define to 1 if // is a file system root distinct from /.])
   fi
-
-  AC_DEFINE_UNQUOTED([DOUBLE_SLASH_IS_DISTINCT_ROOT],
-   $ac_double_slash_root,
-   [Define to 1 if // is a file system root distinct from /.])
 ])