Index: d4x-2.5.7.1/main/nt.cc
===================================================================
--- d4x-2.5.7.1/main/nt.cc
+++ d4x-2.5.7.1/main/nt.cc	2022-07-22 22:17:01.448659138 -0700
@@ -176,7 +176,7 @@
 	if (stat(LOCK_FILE,&stat_buf)==0 && S_ISLNK(stat_buf.st_mode))
 		unlink(LOCK_FILE);
 	LOCK_FILE_D=open(LOCK_FILE,O_TRUNC | O_CREAT |O_RDWR,S_IRUSR | S_IWUSR);
-	if (LOCK_FILE<0 || lockf(LOCK_FILE_D,F_TLOCK,0)) {
+	if (LOCK_FILE_D<0 || lockf(LOCK_FILE_D,F_TLOCK,0)) {
 		if (parse_command_line_already_run(argc,argv))
 			g_print(_("%s probably is already running\n"),VERSION_NAME);
 		if (argc==1)