- Utilize the "showconfig" top-level target.

- Pass __MAKE_CONF=/dev/null to get a pristine output.

tools/build/options/makeman

@@ -5,7 +5,7 @@
 ident='$FreeBSD$'
 
 #
-# show settings | options
+# usage: show { settings | options } ...
 #
 show()
 {
@@ -25,8 +25,10 @@ show()
 		exit 1
 		;;
 	esac
-	make "$@" -f ../../../share/mk/bsd.own.mk SRCCONF=/dev/null -V_ -dg1 |
-	grep ^MK_ |sort |
+	(
+		cd ../../..
+		make "$@" showconfig SRCCONF=/dev/null __MAKE_CONF=/dev/null
+	) |
 	while read var _ val; do
 		opt=${var#MK_}
 		case ${val} in