sizeof(HelloString) does already contain the terminating NULL. Thanks to Hartmut.

Modified: trunk/reactos/lib/hid/hid.c

--- trunk/reactos/lib/hid/hid.c	2005-10-02 13:47:48 UTC (rev 18214)
+++ trunk/reactos/lib/hid/hid.c	2005-10-02 13:54:32 UTC (rev 18215)
@@ -369,14 +369,13 @@

            IN ULONG BufferLength)
 {
   const CHAR HelloString[] = "Hello\n";

-  ULONG StrSize = sizeof(HelloString) + sizeof(HelloString[0]);

   
   if(BufferLength > 0)
   {

-    memcpy(Buffer, HelloString, min(StrSize, BufferLength));

+    memcpy(Buffer, HelloString, min(sizeof(HelloString), BufferLength));

   }
   

-  return StrSize;

+  return sizeof(HelloString);

 }