--- memtest.c.orig	Thu Dec 19 13:43:09 2002
+++ memtest.c	Thu Dec 19 13:42:49 2002
@@ -20,6 +20,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <time.h>
+#include <sys/types.h>
 #include <sys/mman.h>
 #include <signal.h>
 #include <unistd.h>
@@ -249,6 +250,10 @@
 			if (!strcmp (argv[i], "all"))
 			{
 				membytes = 4095 << MB;
+				fprintf (stderr, "%s: ATTENTION: option '%s' might cause a segmentation"
+						 " fault crash on %s because it will try to test as much"
+						 " as 4G of memory even if your system does not have as much"
+						 " memory.\n", argv[0], argv[i], argv[0]);
 				continue;
 			}
 			t = (ui32) strtol (argv[i], &endptr, 0);