Re: [Evolution] Filtering out duplicate messages

[Alessio Bragadini <alessio albourne com>]

On Sat, 2003-01-18 at 14:26, ahimsa wrote:

> With a couple of the lists that I belong to I am finding that I am
> getting two messages - duplicates - and was curious if anybody had found
> a way to filter out the duplicate using Evo's filters? If so, what
> worked for you.

Please search in the list archives, there have been a number of detailed
threads about this. In short: Evo developers feel there is not a safe
algorithm to identify "duplicate messages", so they don't believe this
should be done in Evo. Message-Id headers are not, per se, guaranteed to
be unique on your entire mailbox, although in most cases are.

Being aware of this, then comes my *personal* solution: I have a
procmail rule on the POP server that keeps a cache of seen Message-Ids,
and if a new message matches adds a X-Duplicate header.

:0 Whc: msgid.lock
| formail -D 8192 msgid.cache

:0 af
| formail -I "X-Duplicate: YES"

and a filter inside Evo that deletes messages with such an header. You
can always look inside the Trash folder if you believe you're losing
messages. This is good enough *for me* and BTW is the same configuration
I use to run SpamAssassin.

You may not be able to run procmail and/or not have access to the POP
server. In this case I cannot suggest another solution, apart from
writing a custom script that is activated by an Evo filter.

-- 
Alessio Bragadini <alessio albourne com>
APL Financial Services (Overseas) Ltd