ietf-822
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Re: Angle brackets surrounding Content-ID

2004-11-01 10:12:53

In <200410222024(_dot_)53358(_dot_)blilly(_at_)erols(_dot_)com> Bruce Lilly 
<blilly(_at_)erols(_dot_)com> writes:

On Fri October 22 2004 07:45, Charles Lindsey wrote:

A file in mbox format cannot contain a news article.

The newsreader rn and its derivatives and a number of other
newsreaders save news articles in that format, and can read
messages (which might be "news" messages or "mail" messages)
in that format.

Then Pray Tell what it puts in the "^From " line (that usually contains
the envelope From address plus a time stamp).

Any why is rn saving articles in the first place (or is that for some
archiving facility)? Last time I used rn, it worked online, acquiring
articles on demand from a server, either directly or via NNTP.

There are plenty of hooks within IMAP to enable an implementor to
distinguish Email from Netnews.

No.

For example, it is customary to store news 
articles in folders within a "#news" hierarchy.


Messages also carry flags 
with them which can be used to distinguish various classes of message.

There is no "news" flag or anything remotely resembling
one.

But there is provision for implementation-defined flags. I never claimed
that IMAP could solve this problem 'out of the box' - merely that it
contained 'hooks', such as those flags, which an implementor could (and to
do a proper job should) use to keep track of which articles were 'news'
and which were 'email' as they were moved between IMAP boxes.

Indeed so. The message you are now reading has passed through a
news-to-mail gateway and is therefore, by definition, an email message.

Yes, and the message that it is a response to was also an email
message, whether or not you viewed it in a newsreader.

Correct.


If it is in an
IMAP box, then it depends how it was put there, and that is a matter for
the IMAP implementor.

No. IMAP is a Standards Track protocol that handles messages;
"mail", "news", "hand-crafted" is immaterial. Human users using
a variety of standards-compliant UAs can copy/move messages
between folders at will, as many times as they wish, and there is
no way (or need) to track such movement.

There IS a way (flags, as I have just demonstrated), and there is a need,
because just inspecting the message content is unreliable.

 This too has been
explained to you many times, and you have been informed in
no uncertain terms that any attempt by you to try to impose
any such requirements on IMAP will not pass IESG muster.

I am not trying to impose anything. I am just pointing out that
inplementors of IMAP have to solve this problem somehow, and that it can
be solved rather easily without making any change to the IMAP standards
(though an extension to define a suitable flag could be considered).

It's handling "messages".  When a message is being transported, it
might be transported via a news-specific protocol, or via a mail-specific
protocol, or via a protocol which is non-specific.  Once it has been
transported, it is simply a message.

No. Email and Netnews are distinct media.


If a dual-use agent cannot keep 
track of which medium it is handling, then it is broken, as is any system
which uses a non-specific protocol without suitable tagging.

What are "broken" are your ability to comprehend what has been
explained to you several times by several people, and your ability
to realize that your ability to ram your odd ideas down the IESG's
throats is nil.

Resort to rudeness is always a clear indication that you are losing the
argument.

Return-Path fields are only inserted by SMTP when making final delivery;

Hence the presence of a Return-Path (or of an equivalent "^From " line
arising from an mbox file) is a sure sign that it is an Email.

No; as usual you haven't been paying attention. A message having
been delivered by SMTP to a mail-to-news gateway may very well
still have a Return-Path field when it is transported by a "news"
protocol.

Indeed, the presence/absence of a Return-Path is not conclusive evidence
of whether a message is a news article, but it is considerably more
reliable than the presence/absence of a Newsgroups header.

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
Tel: +44 161 436 6131 Fax: +44 161 436 6133   Web: http://www.cs.man.ac.uk/~chl
Email: chl(_at_)clerew(_dot_)man(_dot_)ac(_dot_)uk      Snail: 5 Clerewood Ave, 
CHEADLE, SK8 3JU, U.K.
PGP: 2C15F1A9      Fingerprint: 73 6D C2 51 93 A0 01 E7 65 E8 64 7E 14 A4 AB A5