[net.mail] Lines starting with period.

blarson@oberon.UUCP (Bob Larson) (12/24/85)

Why can't unix mailers handle lines staring with periods?
(or is it only lines containing a single period and nothing else?)
The way it is rejected varies -- some systems truncate the message
and then return it for misterious reasons (until you figure out the
problem) and others truncate the message and send it on without complaint.
There may even be some that handle it properly, but after a few bounces
your message probably loses anyway.

Is something being done about this as mail handling systems get rewriten?
(The SMTP specifaction includes documentation on how arpanet aviods this
problem.)

-- 
Bob Larson
Arpa: Blarson@Usc-Ecl.Arpa
Uucp: ihnp4!sdcrdcf!oberon!blarson
__________________________________
Unix: An operating system similar to Os-9, but with less functionality
and special features designed to soak up excess memory, disk space and
CPU time on large, expencive computers.
-- Os-9/68000 operating system users manual

dat@hpcnof.UUCP (12/30/85)

>Why can't unix mailers handle lines staring with periods?
>(or is it only lines containing a single period and nothing else?)
>The way it is rejected varies -- some systems truncate the message
>and then return it for misterious reasons (until you figure out the
>problem) and others truncate the message and send it on without complaint.
>There may even be some that handle it properly, but after a few bounces
>your message probably loses anyway.
>						Bob Larson

Actually, it's a holdover from many many years ago when the default
system was a PDP-X and the default terminal was a teletype (remember
those?  No CRT...klunky noisy and expensive to keep full of paper?)
Anyway, a lot of times control characters would be a real pain to
transmit to the host machine, so the software began to accept a 
period by itself on the line to delimit - you guessed it - the
end of file mark!

Lest people think that the defaults have improved any, notice that
on Bell System V the default tty speed if no gettydefs are created
is 300 baud.  yep.  Useful, eh?

As far as a fix, I'd just say DON'T SEND MAIL WITH A "." as the first
and only character on a line.  If you have to send it, prepend it with
a single space or something.

*sigh* meanwhile, here in the future of computing...

				--- Dave Taylor
				Hewlett Packard

				ihnp4!hpfcla!d_taylor

jsdy@hadron.UUCP (Joseph S. D. Yao) (01/03/86)

In article <176@oberon.UUCP> blarson@oberon.UUCP (Bob Larson) writes:
>Why can't unix mailers handle lines staring with periods?
>(or is it only lines containing a single period and nothing else?)

Most Unix mailers can be set to ignore lines with a single dot.
Otherwise, this terminates messages.  If you can determine who
is truncating messages, ask them to fix it.  (e.g., sendmail -i)
-- 

	Joe Yao		hadron!jsdy@seismo.{CSS.GOV,ARPA,UUCP}