Author: Tim Jackson Date: To: exim-users Subject: Re: [exim] How to modify the Subject header
Jakob Hirsch wrote: >> You are, of course, right. I must be going completely barking. Yes,
>> those are in a router. The key point still stands though, that it is
>> cleaner than some other proposed solutions as a) it's simple and b) it's
>> all in one place.
>
> That's only true if all the mail you want the header to be modified is
> handled by a single router.
That's true. I suppose you could probably somehow hack around with a
no_verify router that passes it all, but I haven't tried that.
> But depending on your setup, this could also
> be an advantage because it's more flexible (but would probably better in a
> transport).
A transport has the same problem - it only works if all your mail uses
the same transport (no use for example if you have both local deliveries
and remote forwards)
I can't immediately think of an obvious reason why what I suggested
couldn't go (still in one place) in a system filter, but I may be
missing something. Actually, I may know what it is: although I omitted
it for simplicity when I posted that suggestion, in my real setup the
Subject munging is done on a per-recipient, not per-message basis (so
that only people who really want their mail mangled have it done). So
there is an extra condition about the recipient being routed, which you
couldn't do in a system filter.
I've forgotten some of the background to what I was doing when I was
investigating this, but I know my primary concern was to do the Subject
processing in "one hit" as I don't like passing around temporary
headers/variables more than necessary; it makes it harder to understand
and debug the config.