From: Ken Wellsch <kcwellsc@math.uwaterloo.ca>
Message-Id: <199803241431.JAA09618@math.uwaterloo.ca>
Subject: Re: What's magtape good for anyway?
To: shoppa@alph02.triumf.ca (Tim Shoppa)
Date: Tue, 24 Mar 1998 09:31:48 -0500 (EST)
Cc: edgee@cyberpass.net, pups@minnie.cs.adfa.oz.au
In-Reply-To: <9803240458.AA14216@alph02.triumf.ca> from "Tim Shoppa" at Mar 23, 98 08:58:44 pm
Organization: University of Waterloo, Math Faculty Computing Facility
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Sender: owner-pups@minnie.cs.adfa.oz.au
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Now far for me to be defending 9-track tapes on UNIX systems, and I'm
the first to admit I've not encountered *all* the various methods used
everywhere to write tapes, but it took no time for me years ago to write
a program that would pull blocks off a tape (by trying to read the max
limit block size) and recording the actual block size read.  Oddly enough
when matched with a program that read this "raw format" info, it was sure
trivial to reproduce the tape... but I'm sure I'm missing something.
Luckily on my UNIX systems I am unencumbered by someone else's potentially
proprietary or undocumented "file structure" - both by the system and
by the media. -- Ken

| From owner-pups@minnie.cs.adfa.oz.au  Tue Mar 24 00:09:12 1998
| 
| Most (non-Unix) minicomputer OS's had built-in support for
| ANSI labeled files, which do have filenames (and header bytes to
| specify record sizes and number of records).  Folks who used Unix
| either made their own labeled tape facility (e.g. Ultrix and
| OSF/1 "ltf") or just used "dd" and a lot of hard work.
| 
| The lack of a record structure that is built-in to the Unix filesystem
| really makes things like tape transfers quite irritating.  The rest of
| the world isn't always just a stream of bytes!
| 
| Tim. (shoppa@triumf.ca)