Re: Intent to revive "expires" header - now: draft-welzl-expires-00.txt

In <[email protected]> "Frank Ellermann" <[email protected]> writes:

>- Expires-field = "Expires:" CFWS date-time [CFWS] CRLF
>+ Expires-field = "Expires:" SP date-time CRLF

>| It is additionally defined in a similar way in
>| netnews [5]. 

>Charles wrote it was the other way around, Netnews
>had it first, later MIXER adopted it; fight it out.

Actually, I got it slightly wrong. The Expires header field as defined in
RFC 2156 has the same syntax as we require here (apart from that Netnews
SP, which I think we should omit - we tried, and failed, to get wording
in RFC 2822-bis to fix that).

The _real_ mess in RFC 2156 is that they also re-invented the (widely used
but then undocumented) Netnews Supersedes header field, and gave it the
wrong syntax, necessitating special wording in USEFOR to explain the
discrepancy.

Interestingly, RFC 2156 provides no semantics for the Expires header
(beyond recording the fact that the original X.400 message contained an
'expiry-time'). So any "MAY but MUST NOT" wording you write will probably
do no harm in the case of genuine gated-from-X.400 messages.

>You need a non-empty IANA considerations section to
>update the permanent message header field registry
>with a reference to RFC 3864.

Yes, and the template you provide will need to cover both RFC 2156 and
your new draft.

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