On Thu, 9 Jul 1998, David Sheryn wrote:
> On Thu, 9 Jul 1998, Philip Hazel wrote:
> >
> > > On Mon, 6 Jul 1998, Sean Witham wrote:
> > >
> > > > I would like to be able to use rewrite rules within drivers ! Sometimes I
> > > > only want to perform a rewrite when I know where and how the message is
> > > > going to be delivered.
> >
> > The problem I see with this is that a message may have many recipients,
>
> I'm not sure that I fully understand why this is a problem ? Can you not just
> apply the test to _each_ recipient, and if it matches, re-write, otherwise not ?
Now *I'm* not sure I understand the requirement! I read Sean's comment
to mean that he wanted to rewrite things (headers, envelope, whatever)
only in the copy of a message that was sent to the particular recipient
that had passed through a given director/router. Was this correct, Sean?
I now see that perhaps I misunderstood him, and I have clearly
misunderstood you! Is your requirement correctly stated thus:
If an address is handled by a specific router or director, an option
on that driver is able to request that rewriting take place on the
addresses in the envelope and headers, exactly like the "global"
rewriting rules. This rewriting will happen in the single copy of the
headers, and therefore be visible to all recipients of the message.
In effect this is a private set of rewriting rules that gets triggered
by the success of the router or director.
That is simpler, but unfortunately not much. The problem is that when a
message is deferred, the headers are re-written to the spool file for
use at the next delivery attempt, so all this rewriting would be
recorded, and if you've rewritten envelope addresses, they will be
different next time. Either there has to be some extremely careful
documentation of the consequences of all of this, or this rewriting has
to be done on a copy of the headers and envelope so that they don't get
saved. This is now getting similar to the problem I saw before :-(
--
Philip Hazel University Computing Service,
P.Hazel@??? New Museums Site, Cambridge CB2 3QG,
ph10@??? (sic) England. Phone: +44 1223 334714
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