[ih] Email "autoresponder"

[Jack Haverty]

Good question...

I wrote the MIT-DMS mail daemon, which ran on our PDP-10 ITS machine
back around 1975 or so.  It was the "back-end" to which various other
programs would interface - in particular the "reader" and "composer"
which people used to send and read email.

The daemon, which ran all the time, could process incoming email for a
user when a message arrived for that user, and do virtually anything the
user could imagine, by specifying a program, which the user could write,
to be run by the daemon, on the user's behalf.

Auto-responding was one of the common obvious uses of that facility.  

Some users were very clever though...  One example was a "compiler
mailbox".  A user configured an email address so that the source code of
a program could be sent to that address as a "message", and the
autoresponder would take the message, run it through the compiler, and
return the resulting object code as a reply.  Compilation could take
quite a while and load down the machine -- so this enabled that user to
work on one machine editting and debugging while having a separate
machine do all the heavy lifting of compiling.  Thankfully he survived
when this tactic was discovered by the rest of the group who were always
struggling for computer cycles.

I remember that I first "turned on" the auto-processing of incoming mail
sometime in late spring, announcing to the user community how to write
their own programs to act on their incoming mail - send back a response,
print it out, file it somewhere, whatever.  

Within minutes, an autoresponder was written - the "I'm out of the
office, I'll be back on Tuesday" kind of thing.  It became popular -
lots of people started using it.

Then summer arrived and vacation season....  

One Friday afternoon, several people called it a day and left for a
week's vacation, and enabled their autoresponder as they turned out the
lights.

One of them also sent a message to the whole group, saying "Off on
vacation, see you in a week."

Think about it........

That last message got to the auto-responder of another vacationer, which
dutifully composed and sent a doleful response about being sorry to miss
your message but it will be answered in a week.

The response went to the whole group also - "reply all".  And when the
other vacationers' autoresponders received it, they composed equally
apologetic messages about being sorry to miss your message about being
sorry to miss your message, and sent them to everyone.

Repeat.

Mayhem ensued as the PDP10 processor went to 100% and free disk space
dropped precipitously.

This was 1975 or 1976, can't remember exactly...

IIRC, this experience was part of the motivation for having a guaranteed
unique "Message-ID" and related fields in the header.  A suitably
sophisticated auto-responder could thereby detect loops and do something
sensible.

My simple "autoresponder" wasn't so clever at first.  I wonder if modern
email systems still have this same flaw.

/Jack Haverty
from the soggy, soggy, windy, wet California coast, where power and
phones are out, but the Internet works!


On Fri, 2010-01-15 at 11:29 -0800, Dave CROCKER wrote:
> Folks,
> 
> G'day.
> 
> Just got a query from a reporter relayed to me:
> 
> >>> Do you know anything about the history of the Email-autoresponder?
> >>> I'm currently working on an article about that subject matter and, so far,
> >>> couldn't find any information on how or by whom it was invented. Any hint
> 
> 
> My own MMDF had it in the late 70s but was definitely far from the first.
> 
> I am reasonably certain that sendmail had it long before mine and that its 
> predecessor delivermail might have.
> 
> But I do not remember whether other email software had such a feature back then.
> 
> Do any of you?
> 
> Thanks.
> 
> d/
>