Re: [ietf-822] "--" first in lines to indicate start of signature

Russ Allbery <eagle@eyrie.org> Mon, 04 January 2016 23:33 UTC

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From: Russ Allbery <eagle@eyrie.org>
To: Hector Santos <hsantos@isdg.net>
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Cc: ietf-822@ietf.org, "Murray S. Kucherawy" <superuser@gmail.com>, Jacob Palme <jpalme@dsv.su.se>
Subject: Re: [ietf-822] "--" first in lines to indicate start of signature
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Hector Santos <hsantos@isdg.net> writes:

> But do they use "-- " automatically or is it user-defined (added)?

Automatically.  You specify the contents of the signature (via various
ways), and the process of appending the signature coded in the client
automatically adds the "-- " delimiter line.

> Yes, the history is long there but also for other formats or even no
> "tag" formats at all, e.g.; just with a tab and name, perhaps.

I'm probably arguing with something you're not actually saying, so feel
free to ignore me if that's the case.

But I feel like you're misunderstanding the degree to which this is part
of the netnews article format.  This is not a random convention that just
some people use on the netnews side; it's built into every netnews client
I know of that supports signatures, and is very widely supported on the
reading side as well.  (For example, my client does syntax highlighting of
the signature block, greying it out, and supports automatically omitting
the signature from quoted follow-ups.)  It was commmon for people on
netnews to point out to others when the signature delimiter was mangled
(missing the trailing space, for instance), and there are netiquette
conventions for acceptable length and related issues.  (The Google search
term is "McQuary limit".)

It may be just one of many conventions in email.  It is an actual,
interoperable standard in the netnews world, albeit an ad hoc one rather
than a formalized one.  Insofar as mail and netnews share a common message
format, "-- " deserves a bit more special attention from the implementor
than, say, random examples of FidoNet conventions.  Proper handling is a
quality of implementation issue if you ever touch netnews.

-- 
Russ Allbery (eagle@eyrie.org)              <http://www.eyrie.org/~eagle/>