Properly sanitize --menu results (guards against Gtk library warnings from

X11 side of things from bleeding into Xdialog(1) stderr output). It should
be duely noted that such errors are not a by-product of anything in the
Xdialog(1) utility or API, but optional libraries that it can link against
(such as Gtk1 versus Gtk2; if you compile xdialog from ports against Gtk2
AND misconfigure your fonts or generally make Gtk2 unhappy, these warning
messages can bleed into the captured stderr -- that is we we sanitize!).

usr.sbin/bsdconfig/share/device.subr

@@ -645,7 +645,12 @@ f_device_menu()
 
 	[ "$errexit" ] && set -e
 
-	[ $retval -eq 0 ] && echo "$mtag" >&2
+	if [ $retval -eq 0 ]; then
+		# Clean up the output of [X]dialog(1) and return it
+		setvar DIALOG_MENU_$$ "$mtag"
+		mtag=$( f_dialog_menutag )
+		echo "$mtag" >&2
+	fi
 
 	return $retval
 }

usr.sbin/bsdconfig/share/media/tcpip.subr

@@ -1399,6 +1399,8 @@ f_device_dialog_tcp()
 					2>&1 >&$DIALOG_TERMINAL_PASSTHRU_FD
 				)
 				local retval=$?
+				setvar DIALOG_MENU_$$ "$cp"
+				cp=$( f_dialog_menutag )
 				f_dprintf "retval=%u mtag=[%s]" $retval "$cp"
 
 				if [ $retval -eq 2 ]; then