<DKIM> Why is OfflineIMAP working "in reverse"?

[Nicolas Sebrecht]

On Mon, Jul 13, 2015 at 02:49:33PM -0700, Tom Scott wrote:

>    Honestly I'm not sure. I just noticed offlineimap telling me it was
>    syncing messages from my local Maildir back to the remote server
>    (Gmail), and all the message numbers are negative. Reading a bunch of
>    guides it seems like offlineimap can potentially screw with mailboxes
>    (like delete messages), so I was unsure as to whether I was
>    encountering a problem that could cause damage. Ran offlineimap all day
>    and it hasn't seemed to do anything nefarious yet, though. Just wanted
>    to get a little more clarification on what's going on.

Sure. The numbers are the UIDs with respect to the IMAP protocol. They
are assigned by the IMAP server (must be positive).  OfflineIMAP
temporary assign negatives numbers (no conflicts) to the mails to upload
to the server before they are assigned their real UID by the server.

-- 
Nicolas Sebrecht