Date   : Fri, 01 May 2009 23:20:13 +0100
From   : philpem@... (Philip Pemberton)
Subject: Preservation of information (floppy discs, etc.)

Jules Richardson wrote:
> Argh - I'm suffering from 'too many words' today so will read the rest of the 
> message later...

I've got that, and "fuzzy head syndrome", "can't be bothered anymore 
syndrome", "sick of arguing with customer (dis)service reps syndrome", and 
possibly a little "the weather's crap so I feel crap syndrome". It's been a 
fun day. :)

I found my notes, so here's the concise, summarised, OED version:

Basically, the idea was to have a completely open-source hardware "pod" that 
anyone who could wield a soldering iron could build and use to image whatever 
discs they had. Then people can send those images to each other, without 
needing XYZ Machine Type 12345 to make a copy of the disc - you just need the 
"pod".

So you have a way to take an exact image of the disc (assuming the drive works 
properly) and recreate a reasonable facsimile of it in another location. If 
you know the format (say it's an Amiga, BBC or PC disc) then you can decode it 
back into files again, or decode to bit level, re-encode and write it back out 
again (essentially re-timing -- like what Ethernet hubs and USB active 
extension cables do).

Then have a piece of software that deals with decoding, remastering, and 
basically lets you play with the disc at an unbelievably low level. Copy 
protection ceases to have any meaning... :)

The Software Preservation Society are doing something similar with the Amiga. 
Basically reading discs at magnetic-transition level (using the Amiga FDC, 
which is a neat trick) and then creating an image of the disc that stores 
everything, *including* the copy protection.

Someone raised a point about Don Maslin's archive -- AIUI the situation was 
that he had boot discs for most every CP/M machine (and a few others besides). 
When he passed away, his wife's first act was (allegedly) to dump all the 
discs in a skip.

When you're dealing with files, you don't really have that problem. Archiving 
ends up being an issue of distribution -- "Here's my FTP site, these are all 
my bootdiscs, if you want to mirror them email foo@... and I'll give you 
Rsync access". The more mirrors you have, the less the chance of all of them 
disappearing...

The thing about having a magnetic image is that you know *everything* about 
that disc that you can read and write with normal hardware. So if Joe Bloggs 
comes up with a cool new way to decode the data on an XYZ format disc, the 
magnetic image should be all he needs to try his idea out.

> ... but JOOI do you see threading problems over on classiccmp, too? I first 
> noticed problems there, then on this list; I'm wondering if it's a TB bug 
> related to message frequency / traffic rather than something to do with broken 
> clients on the part of the original sender. If it's not the latter, I'd love 
> to find a fix!

TBird seems to thread based on message-ID (and the References: and 
In-Reply-To: headers), and some lists don't pass that through. MessengerPro 
(on the RISC OS platform) got around this by allowing you to thread by subject 
as well (which actually worked better than you might think).

Half the problem seems to be people using Yahoo web-mail, which doesn't appear 
to handle the In-Reply-To:/References: headers in an RFC-compliant way. It 
appears a few other folk are sending mail via the Arcade BBS, which doesn't do 
this either. It would be nice if RFCs were followed, but I've given up whining 
about it. That's also known as "the software I wrote follows the relevant RFCs 
so I don't care syndrome" :)

Gmail, interestingly, doesn't seem to suffer from this problem (thank $DEITY!)

I'm going to shut up now, before the Flaming Pitchfork Brigade get ready to 
burn me at the stake :)

-- 
Phil.
philpem@...          
http://www.philpem.me.uk/