+
+case ".$with_fallback" in
+(.|.no)
+ FALLBACK_LIST=
+ ;;
+(.yes)
+ AC_MSG_WARN(expected a list of terminal descriptions)
+ ;;
+(*)
+ FALLBACK_LIST=`echo "$with_fallback" | sed -e 's/,/ /g'`
+ ;;
+esac
+
+USE_FALLBACKS=
+test -z "$FALLBACK_LIST" && USE_FALLBACKS="#"