On 10/8/2010 11:47 AM, nan wich wrote:
> @Gerhard: 80 lines was how long a punch card was. What a ridiculous
> reason to use 80 any more. Are you even old enough to have ever seen a
> punch card? I almost forgot, the original IBM System/3 had punch cards

Yes, Nancy, there are actually a few adults on this list. Though I doubt
many of us are old enough to have actually USED a punch card, since
people who did work on punch cards should be pretty close to retirement
age by now.

Nope!

Used them in 1985 in a course, where the norm was to write your code
on a sheet and then send it to an operator who will punch it and then it
would be compiled from cards.

That was a training course though, terminals were available at the same
time.

Also saw vendor system engineers who were puzzled for a couple of days
and could not boot a new system because it was the first of its kind in that
region NOT to have a punched card reader.

Saw at least one client in the early 90s who had working punched card
readers and JCL jobs for them.

Still a decade or two until I retire.

80 characters was the common width of monitors, which descended from
punch cards, but is also pretty close to the 72 character width of the
common typewriter (pica, if I remember right) with standard margins.

An 80 character card had a 6 character sequence number, for some
languages (e.g. COBOL) so if the card deck falls on the floor you can do
a sort run and it will sort it correctly. Column 7 was for comments (an *
in COBOL for example). This leaves 73 characters.

Not sure if that was related (can't use the full 80 on a terminal card image?)

RFC
2822 imposed the limit (as a SHOULD not MUST) because many terminals
failed to wrap on their own, and terminals often had 80 CPL in order to
be standard. Though many terminals also had 132 or, if you were
unfortunate enough to use a VIC-20 (and maybe a PET, I forget) you could
get 40 CPL.

132 was much later, and was not a standard. Mostly some DEC VT, or that is where it started.

Also, RFC2822 is still in effect; if an email message is in text/plain,
it is polite to go ahead and wrap at 78 per the spec. If your message is
text/html then wrapping is pointless.