Group Param on IMAP group

Group Param on IMAP group

[Harry Putnam]

I recently started getting one group from an IMAP server running
Cyrus software.  I had this same group as a normal nnml group before
and still do for now.

I've  moved the Group Parameters from the nnml group to the
IMAP group bodily.

On pressing `G p' on the IMAP group I find gnus has alread inserted a
group param:

((uidvalidity . "949203895"))

I lopped one paren off and added my own stuff below:
((uidvalidity . "949203895")
   (to-address . "lula@onelist.com")
   (banner . "^--+ ONElist Sponsor --+\n\n\\(.\\|\n\\)*"))

Anyone know what the gnus insert means?  This server has an anonymous
login.

Re: Group Param on IMAP group

[Kai Großjohann]

Harry Putnam <reader@newsguy.com> writes:

> Anyone know what the gnus insert means?  This server has an
> anonymous login.

It is possible to identify a message by id, but the ids may change.  I
think the idea is to have article numbers, and these can change when
you delete a message in the middle of a folder.

So the IMAP server is required to tell you a `uidvalidity' value, and
as long as that value is the same, the old article numbers are still
valid.  When the uidvalidity value changes, the article numbers may
have changed, as well.

I think.

kai
-- 
A large number of young women don't trust men with beards.  (BFBS Radio)

Re: Group Param on IMAP group

[Jeff Senn]

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Kai.Grossjohann@CS.Uni-Dortmund.DE (Kai Großjohann) writes:

> It is possible to identify a message by id, but the ids may change.  I

Yes.

> think the idea is to have article numbers, and these can change when
> you delete a message in the middle of a folder.

It's not really to support this case of renumbering... the "article
numbers" (which don't really have to be numbers, theoretically :-) ) are
really IDs that are not reused while the group/folder exists.

Because IMAP was designed for many connected sessions as well as
disconnected operation, it is important to detect the case where a
group has been deleted and another group recreated with exactly the
same name.

> So the IMAP server is required to tell you a `uidvalidity' value, and
> as long as that value is the same, the old article numbers are still
> valid.  When the uidvalidity value changes, the article numbers may
> have changed, as well.

Yes. More strongly : if uidvalidity changes, NO info about the previous
group or anything in it is relevant to the new group.

-- 
-Jas