--- a/os.c	Sun May 07 01:33:40 2006 +0200
+++ b/os.c	Sun May 07 13:24:07 2006 +0200
@@ -13,7 +13,7 @@
 int max_depth = 0;
 int min_depth_period = 0;
 int max_depth_period = 0;
-struct Map * actual_map;
+struct Map * actual_map = NULL;
 
 
 void ReadMap(struct Map *M, char *FileName)
@@ -138,7 +138,8 @@
 {
 	fprintf(stderr, "Percent: %2.12f, depth: %i-%i\n", percent_to_show,
 		min_depth_period, max_depth_period);
-	ShowMap(actual_map);
+	if(actual_map != NULL)
+		ShowMap(actual_map);
 	fflush(stderr);
 	min_depth_period = MAX_STEPS;
 	max_depth_period = 0;