Re: Syntax validation of articles by injecting agents

["Charles Lindsey" <chl@xxxxxxxxxxxxxxxx>]

In <873a2lz4dk.fsf@xxxxxxxxxxxxxxxxxxxxx> Russ Allbery <rra@xxxxxxxxxxxx> writes:

>"Charles Lindsey" <chl@xxxxxxxxxxxxxxxx> writes:

>> Eh? How does it imply that? If there are no Content-* headers, then
>> there is no requirement for MIME-Version.

>See Julien's post:

>| NN for instance does not generate MIME-Version: header fields
>| although "user agents MUST meet the definition of MIME conformance"
>| ("a mail user agent that is MIME-conformant MUST always generate
>| a "MIME-Version: 1.0" header field in any message it creates").
>| I believe this sentence applies to news user agents too, otherwise
>| a reference to MIME is useless.

>The first quoted statement is from RFC 5536 section 2.3, with an
>accompanying reference to RFC 2049.  The second quoted statement is from
>RFC 2049 section 2.

But I don't think RFC 2049 ever intended to imply that MIME-Version was
needed for a message that did not actually use any of the MIME features.
As evidence of that, I can cite RFC 2047, which states:

   (4) A MIME-Version header field is NOT required to be present for
       'encoded-word's to be interpreted according to this
       specification.  One reason for this is that the mail reader is
       not expected to parse the entire message header before displaying
       lines that may contain 'encoded-word's.

>Now that I think about it, though, this only places a requirement on the
>user agent.  It doesn't require that the server reject the message, so I
>think the original problem isn't actually that significant of a problem.
>MIME-compliant agents, such as injecting agents, are allowed to accept
>non-MIME messages.

Exactly.

>> But aren't injecting agents allowed to remove a Path header that is
>> received?


>Injecting agents are specifically discouraged (SHOULD NOT) from fixing or
>remove any header fieldss other than Path.

Which is fair enough, but gives leeway for Paths to be removed, which
copes with the particular problem that was raised. For sure, many
injecting agents DO remove it regardless, because they regard it as an
"infringement of their rights" :-) .

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
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