ax_posix_shell.m4 revision 1.1.1.3
1# SPDX-License-Identifier: FSFAP 2# 3# AX_POSIX_SHELL 4# ------------- 5# Check for a POSIX-compatible shell. 6# 7# LICENSE 8# 9# Copyright (c) 2021 Internet Systems Consortium 10# 11# Copying and distribution of this file, with or without modification, are 12# permitted in any medium without royalty provided the copyright notice 13# and this notice are preserved. This file is offered as-is, without any 14# warranty. 15 16AC_DEFUN([AX_POSIX_SHELL], 17 [AC_CACHE_CHECK([for a POSIX-compatible shell], [ac_cv_prog_shell], 18 [ac_test_shell_script=' 19 test "$(expr 1 + 1)" = "2" && 20 test "$(( 1 + 1 ))" = "2" 21 ' 22 23 for ac_cv_prog_shell in \ 24 "$CONFIG_SHELL" "$SHELL" /bin/sh /bin/bash /bin/ksh /bin/sh5 no; do 25 AS_CASE([$ac_cv_prog_shell], 26 [/*],[ 27 AS_IF(["$ac_cv_prog_shell" -c "$ac_test_shell_script" 2>/dev/null], 28 [break]) 29 ]) 30 done 31 ]) 32 AS_IF([test "$ac_cv_prog_shell" = "no"], 33 [SHELL=/bin/sh 34 AC_MSG_WARN([using $SHELL, even though it does not conform to POSIX]) 35 ], 36 [SHELL="$ac_cv_prog_shell" 37 ]) 38 AC_SUBST([SHELL]) 39 ]) 40