Re: [usefor] Trailing whitespace in header fields

Russ Allbery <eagle@eyrie.org> Mon, 08 August 2016 02:09 UTC

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From: Russ Allbery <eagle@eyrie.org>
To: Julien =?utf-8?Q?=C3=89LIE?= <julien@trigofacile.com>
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Subject: Re: [usefor] Trailing whitespace in header fields
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Julien ÉLIE <julien@trigofacile.com> writes:

> It means that trailing whitespace SHOULD NOT be present in Netnews
> header field lines.  (RFC 3977 uses a stricter definition of
> "unstructured" than RFC 5536!)

> Is it really a rule to enforce for Netnews articles?  And does someone
> know why this is not mentioned at all in RFC 5536?

I'm not sure how much we discussed this at the time, but normally trailing
whitespace is a SHOULD NOT generate because it tends to get mangled by
software and is very fragile.  But if that's the only justification (and I
can't think of another off-hand), it's not the sort of thing for a server
to enforce, just for a client to not do because it may not survive
transit.  If the server *can* handle it, it probably should try.

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