Ray Banana <rayban@raybanana.net> writes:
> * Julien ÉLIE wrote:

>> Maybe the best move here is to use the "preferred format" per RFC 3977
>> with :bytes and :lines advertised in LIST OVERVIEW.FMT only when the
>> news reader has previously used CAPABILITIES? And we keep Bytes: and
>> Lines: otherwise.

> I'm not sure of the correlation between clients using CAPABILITIES and
> clients using LIST OVERVIEW.FMT. In slrn's case it would certainly work.

The underlying issue is that LIST OVERVIEW.FMT changed somewhat during its
standardization process from what it was like before RFC 3977,
specifically to add the metadata syntax. CAPABILITIES was added in RFC
3977, so older clients that don't understand the new syntax presumably
also won't send that command.

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

Please post questions rather than mailing me directly.
<https://www.eyrie.org/~eagle/faqs/questions.html> explains why.