ax_posix_shell.m4 revision 1.1.1.2 
1# AX_POSIX_SHELL
2# -------------
3# Check for a POSIX-compatible shell.
4#
5AC_DEFUN([AX_POSIX_SHELL],
6	 [AC_CACHE_CHECK([for a POSIX-compatible shell], [ac_cv_prog_shell],
7			 [ac_test_shell_script='
8			  test "$(expr 1 + 1)" = "2" &&
9			  test "$(( 1 + 1 ))" = "2"
10			  '
11
12			  for ac_cv_prog_shell in \
13			    "$CONFIG_SHELL" "$SHELL" /bin/sh /bin/bash /bin/ksh /bin/sh5 no; do
14			    AS_CASE([$ac_cv_prog_shell],
15				    [/*],[
16				      AS_IF(["$ac_cv_prog_shell" -c "$ac_test_shell_script" 2>/dev/null],
17					    [break])
18				    ])
19			  done
20			 ])
21	  AS_IF([test "$ac_cv_prog_shell" = "no"],
22		[SHELL=/bin/sh
23		 AC_MSG_WARN([using $SHELL, even though it does not conform to POSIX])
24		],
25		[SHELL="$ac_cv_prog_shell"
26		])
27	  AC_SUBST([SHELL])
28	 ])
29