[TUHS] long lived programs

Steve Johnson scj at yaccman.com
Fri Apr 6 14:29:49 AEST 2018

Just to make life more interesting, in the early days anything other
than letters and numbers were often different for different
manufacturers.  I seem to recall Bell Labs buying a custom "print
chain" in order to get enough special characters to handle printing
programming languages (Doug, this was almost before my time -- do you
remember the details?).   I remember there was a device that could
print the contents of a punched card on the punched card itself.  It
had a number of quirks, including that it only printed 40 (or was it
50) columns of the 80-column card, and had virtually no special
symbols.  We quickly became adept at looking at the garbled
subsection of the card and intuiting which card it really was...

I became all to familiar with that card printer during one summer
job.  I was working for Stan Brown, who had written a symbolic
algebra system in assembler.   It was a real tour-de-force, and
contained several thousand punched cards.  When I started my summer
job, Stan made a copy of all the cards for me, so we each had a
copy.   Shortly after I arrived, the comp center announced a
brand-new feature -- permanent disc storage!  (actually, I think it
was a drum...).   Stan and I were excited about the possibility that
we could edit the single copy of the program and not have to keep our
copies in sync, so we loaded the cards into the file.  There was a
crude editor that would allow you to make one pass through the file in
order, deleting lines or adding card images after certain line
numbers.   You needed a printout of the file that told you the line
numbers, but the printout was much easier to handle than the punched

A couple of days after the program was safely on the drum, Stan threw
out his card deck, assuming that I had the backup copy.  At about the
same time, I threw out my card deck, assuming that Stan had a copy. 
We discovered this the hard way when I tried to do a fairly
substantial edit of the file on disc.  It turned out that the editor
only worked correctly when you wrote the edited file into a new
file.  If you didn't specify a new file, it attepted to do the edit
on top of the file as it edited, creating a jumble of fragments of the
original file -- typically 3-10 lines.   By the time we realized
this, the file was good and trashed, and we had no backup.   But we
did have a listing...

So I punched out the mangled file onto cards, and fed them through the
card printer, and spent the weekend comparing line by line -- in many
cases, I could simply move the punched cards into the proper order,
but I did plenty of card punching as well.  Amazingly, I managed to
get it working again, and Stan and I kept updated punched cards
throughout the summer...


----- Original Message -----
From: "Random832" <random832 at fastmail.com>
To:<tuhs at minnie.tuhs.org>
Sent:Thu, 05 Apr 2018 22:03:40 -0400
Subject:Re: [TUHS] long lived programs

 On Thu, Apr 5, 2018, at 17:38, Bakul Shah wrote:
 > May be case itself is such a historical artifact? AFAIK all
 > scripts are without case distinction.

 Greek and Cyrillic both have cases. And the Hiragana/Katakana
distinction in Japanese is similar to case in some ways (including
limited computer systems using only one)

 Full list of scripts in unicode that have case distinctions (based on
analyzing character names): Adlam, Armenian, Cherokee, Coptic,
Cyrillic, Deseret, Georgian, Glagolitic, Greek, Latin, Old Hungarian,
Osage, and Warang Citi.

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