diff options
Diffstat (limited to 'm4/double-slash-root.m4')
| -rw-r--r-- | m4/double-slash-root.m4 | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/m4/double-slash-root.m4 b/m4/double-slash-root.m4 new file mode 100644 index 0000000..dfd3921 --- /dev/null +++ b/m4/double-slash-root.m4 @@ -0,0 +1,38 @@ +# double-slash-root.m4 serial 4 -*- Autoconf -*- +dnl Copyright (C) 2006, 2008-2016 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. + +AC_DEFUN([gl_DOUBLE_SLASH_ROOT], +[ + AC_REQUIRE([AC_CANONICAL_HOST]) + 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), + # 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 $host in + *-cygwin | i370-ibm-openedition) + gl_cv_double_slash_root=yes ;; + *) + # Be optimistic and assume that / and // are the same when we + # don't know. + gl_cv_double_slash_root='unknown, assuming no' ;; + esac + else + set x `ls -di / // 2>/dev/null` + if test "$[2]" = "$[4]" && wc //dev/null >/dev/null 2>&1; then + gl_cv_double_slash_root=no + else + gl_cv_double_slash_root=yes + fi + fi]) + if test "$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 +]) |