1 # Find a POSIX-conforming shell.
3 # Copyright (C) 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 # If a POSIX-conforming shell can be found, set POSIX_SHELL and
12 # PREFERABLY_POSIX_SHELL to it. If not, set POSIX_SHELL to the
13 # empty string and PREFERABLY_POSIX_SHELL to '/bin/sh'.
15 AC_DEFUN([gl_POSIX_SHELL],
17 AC_CACHE_CHECK([for a shell that conforms to POSIX], [gl_cv_posix_shell],
18 [gl_test_POSIX_SHELL='
34 test "[$](echo foo)" = foo &&
39 (set x && func_ret_success y && test x = "[$]1")
41 for gl_cv_posix_shell in \
42 "$CONFIG_SHELL" "$SHELL" /bin/sh /bin/bash /bin/ksh /bin/sh5 no; do
43 case $gl_cv_posix_shell in
45 "$gl_cv_posix_shell" -c "$gl_test_POSIX_shell" 2>/dev/null && break;;
49 if test "$gl_cv_posix_shell" != no; then
50 POSIX_SHELL=$gl_cv_posix_shell
51 PREFERABLY_POSIX_SHELL=$POSIX_SHELL
54 PREFERABLY_POSIX_SHELL=/bin/sh
56 AC_SUBST([POSIX_SHELL])
57 AC_SUBST([PREFERABLY_POSIX_SHELL])