On Thu, 18 Oct 2012, Phil Pennock wrote:
> From: Phil Pennock <exim-users@???>
> To: Luca Bertoncello <lucabert@???>
> Cc: exim-users@???
> Date: Thu, 18 Oct 2012 07:34:03
> Subject: Re: [exim] Avoiding duplicated E-Mails in forwarding
> Reply-To: exim-users@???
...
> You're at the level where you've taken the messages outside Exim's
> control enough that you need to move the decisions about what
> recipients should be honoured out of Exim's control too, and write
> a daemon which tracks "Message-Id" and recipient headers, so can
> be asked for each $h_Message_Id: and recipient pair, if this
> recipient should be re-routed to /dev/null instead.
Straying even further away from exim, the Cyrus IMAP server has this
capability. From the man page for imapd.conf:
duplicatesuppression: 1
If enabled, lmtpd will suppress delivery of a message
to a mailbox if a message with the same message-id
(or resent-message-id) is recorded as having already
been delivered to the mailbox. Records the mailbox
and message-id/resent-message-id of all successful
deliveries.
--
Dennis Davis, BUCS, University of Bath, Bath, BA2 7AY, UK
D.H.Davis@??? Phone: +44 1225 386101
