--- dx-4.4.4/src/uipp/dxuilib/EditorWindow.C.orig	2018-05-16 05:56:15.975434667 +0200
+++ dx-4.4.4/src/uipp/dxuilib/EditorWindow.C	2018-05-16 05:56:19.555623422 +0200
@@ -5997,7 +5997,7 @@
     //
     const char *tmpdir = theDXApplication->getTmpDirectory();
     int tmpdirlen = STRLEN(tmpdir);
-    if (!tmpdirlen) return FALSE;
+    if (!tmpdirlen) return NUL(char*);
     if (tmpdir[tmpdirlen-1] == '/') {
 	sprintf(netfilename, "%sdx%d.net", tmpdir, getpid());
 	sprintf(cfgfilename, "%sdx%d.cfg", tmpdir, getpid());