Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!ogicse!oregon!jmeissen
From: jmeissen@oregon.oacis.org (John Meissen)
Newsgroups: comp.sys.amiga
Subject: Re: Write protect mechanisms (was Re: Virus)
Message-ID: <446@oregon.oacis.org>
Date: 10 Apr 90 21:48:41 GMT
References: <9004102044.AA12596@jade.berkeley.edu>
Organization: Oregon Advanced Computing Institute (OACIS), Beaverton, OR
Lines: 20

In article <9004102044.AA12596@jade.berkeley.edu> JTREWORGY@Wesleyan.BITNET (James Treworgy) writes:
>> Proper fail-safe design would have reversed the modes, so that a closed tab
>> meant write-protect. A failure in that case would mean a default
>> of write-protect.
>
>That's one way to look at it, but if, as you say, the mode had been reversed,
>your drive would be useless if the mechanism broke down (you wouldn't be able
>to write to disks). As it is, you are just in a situation where you can't write
>protect disks if it breaks. I think this has fewer negative effects than not
>being able to write at all (all the disks I use extensively are write enabled
>anyway, for obvious reasons).

This could be argued many ways. But with the formaer method a failure isn't
really catastrophic. Unfortunately with the current situation you have no way
of detecting a failure until files start mysteriously disappearing from
supposedly write-protected disks. If the mechanism were reversed, as I proposed,
then you could still read your data from the disk, allowing you to run in a 
limited way. As soon as you tried to write to the drive the failure would be
evident and you could get it fixed. Assuming you had more than one drive, having
one operate in read-only mode temporarily would be safe, not catastrophic.