Date   : Fri, 08 Oct 2004 00:06:17 +0100
From   : jgh@... (Jonathan Graham Harston)
Subject: Re: Load and execution

> I don't think this is documented anywhere, but setting b7 of the first
> character of any filename (i.e. offset 08, 10, 18 etc) stops the file from
> being listed by *CAT.  It can still be seen by *INFO *.* or *EX though.
> 
> Anyone know whether this was an official part of the DFS spec, whether it
This is a side-effect from the way DFS lists the catalogue in alphabetical
order. The catalogue is not sorted. DFS loops through the catalogue
displaying whichever entry is next in alphabetical order until all are
displayed. It sets bit 7 of the character 0 in the copy of the catalogue
in memory to note that this entry has been displayed.
Consequently, if character 0 bit 7 is set the DFS *CAT code thinks it has
already been displayed, and so doesn't ever display it!
-- 
J.G.Harston - jgh@...                - mdfs.net/User/JGH
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