dnl FC_EXPAND_DIR(VARNAME, DIR)
dnl expands occurrences of ${prefix} and ${exec_prefix} in the given DIR,
dnl and assigns the resulting string to VARNAME
dnl example: FC_EXPAND_DIR(LOCALEDIR, "$datadir/locale")
dnl eg, then: AC_DEFINE_UNQUOTED(LOCALEDIR, "$LOCALEDIR")
dnl by Alexandre Oliva 
dnl from http://www.cygnus.com/ml/automake/1998-Aug/0040.html
dnl GCS: I stole this from freeciv.
AC_DEFUN(FC_EXPAND_DIR, [
        $1=$2
        $1=`(
            test "x$prefix" = xNONE && prefix="$ac_default_prefix"
            test "x$exec_prefix" = xNONE && exec_prefix="${prefix}"
            eval echo \""[$]$1"\"
        )`
])