HIGHESTMODSEQ tracking

[Michael M Slusarz]

Quoting Kostya Vasilyev <kmansoft at gmail.com>:

>> This is getting a bit off-topic on this list... but Gmail does a LOT of
>> things wrong.  Head over to one of the IMAP lists for further information.
>>
>
> This is just one glaring example. Maybe you've ran into more than I have.
>
> In any case, the point stands - with Gmail, it's much easier to be
> confident, from actual testing, that things works a certain way.
>
>
>>
>> If you are testing against Gmail as the gold standard as to how a IMAP
>> server should operate,
>
>
> I never said or implied that. In fact, I pointed out a serious issue with
> Gmail's IMAP IDLE implementation, which means the exact opposite of holding
> it as a gold standard.
>
>
>> I can safely say you are Doing It Wrong.
>
>
> It seems you enjoy pointing out to people when they're "wrong" or
> "incorrect" so much, you actually put meaning into their words that's not
> there? Or it it just me?

I was just trying to point out that this statement is very  
dangerous/incorrect:

"In any case, the point stands - with Gmail, it's much easier to be  
confident, from actual testing, that things works a certain way."

Gmail behavior may/can/will change overnight, and you will have no  
idea.  It makes a lot more sense to pick a local server of a known  
version, that has deterministic behavior, to develop with.

>>  For the "more than 50% market share" of Dovecot / Cyrus, do you have a
>>> breakdown by version number? At least in terms of 1.* vs 2.0 and higher?
>>>
>>
>> I do not.
>
>
> And without being able to get a version number from a Dovecot session (or
> so it seems to me -- nothing returned from ID...).... it looks kind of sad.

ID extension is pretty much worthless for version identification.  It  
is trivially spoofed -- and some servers do exactly this in the real  
world.  All it takes is one server/version to be spoofed to make that  
data worthless.

It's possible to do some level of basic version sniffing by things  
like banner messages, Human-readable responses, CAPABILITY lists, and  
ordering of responses to various commands.  However, this is really  
only useful for broad statistical surveys and not precise version  
determination.

I have been able to work around all IMAP issues that have been  
reported to us solely based on the data returned, rather than knowing  
what IMAP server/version I am connected to.

michael