From:	MORRIS JP <jpmorris AT csm DOT uwe DOT ac DOT uk>
Date:	Mon, 10 Feb 1997 13:16:34 GMT
Message-Id:	<199702101316.NAA24978@milly>
To:	opendos AT mail DOT tacoma DOT net
Subject:	[opendos] Re: [opendos-developer] unix directory links in OD???
Sender:	owner-opendos AT mail DOT tacoma DOT net

> From owner-opendos AT mail DOT tacoma DOT net Mon Feb 10 13:04:36 1997
> From: mharris AT blackwidow DOT saultc DOT on DOT ca
> Date: Mon, 10 Feb 1997 07:28:41 -0500 (EST)
> X-Sender: root AT capslock DOT com
> To: "Paul J. Thompson" <thomppj AT okstate DOT edu>
> Cc: opendos-developer AT mail DOT tacoma DOT net
> Subject: Re: [opendos-developer] unix directory links in OD???
> Mime-Version: 1.0
> 
> On Thu, 6 Feb 1997, Paul J. Thompson wrote:
> 
> > I was thinking today how useful the directory links from unix would be in 
> > dos (OD).  Now, I don't remember the exact name of what they are called, 
> > but it should be added to the improvement list.  I am sure it would be a 
> > very simple addition...
>
>
> You COULD manually create 2 directory entries in a dir on your
> hard disk that would point to the same file in your FAT (a
> hardlink), however any disk maintenance software (such as CHKDSK,
> SCANDISK, NDD) will detect this and label it as an error.  Ever
> hear of crosslinked files?
> 

I have achieved this on a floppy disk using Norton Utility.

I simply changed the starting cluster and length fields of a dummy file I
created, and lo, a link!

However, as you say, chkdsk goes psychotic when it notices this, and deleting
the file tends to create problems.

I was intending to create a utility that produced a file in the root directory
containing a list of all links, and hooked into the DOS API.

When something bad occurs (deletion, low level access) all the links are
removed until the thing has finished, then they are reconstructed from the
link table in the root.

It would have been quite dangerous to do though.  That is why I would prefer
to get a filesystem from Caldera instead of Mr Nobody..

> A symlink under DOS is impossible on FAT without the IFS API, but
> would be a hack (ala microsloth) even if it were to be
> implemented in DOS FAT.  Either way, those diagnostic programs
> would still have a fit and destroy files on you.
>  
> 
> 
> Mike A. Harris        |             http://blackwidow.saultc.on.ca/~mharris
> Computer Consultant   |    My webpage has moved and my address has changed.
> My dynamic address: http://blackwidow.saultc.on.ca/~mharris/ip-address.html
> mailto:mharris AT blackwidow DOT saultc DOT on DOT ca
> 
> Xwindows: Forget '95.  Use a REAL GUI.
> 
> 

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