Philip Hazel wrote:
>
> > >
> > do the term fork and vfork come to mind ?
>
> No. I can't see that that would help at all. It's the fact that only one
> copy of the headers exist and are saved for retries that makes this
> hard.
>
I used them only to illistrate the options regarding cloneing email
compared
with that of cloning a process. vfork does not actualy clone the whole
process.
> There are also all sorts of horrid complications. Consider a message to
> two recipients containing
>
> To: x@abcd, y@???
>
> Now, if you clone that at the start so that there are two copies the
> headers, and then if routing of x@abcd discovers that this is an
> abbreviated address which really should be x@???, then that
> rewrite won't get done in the copy of the headers being used for the
> y@??? address. So the only way to do this "properly" would be
>
> (a) Have one copy of the headers and addresses.
> (b) Do all the routing and directing, and any ...
> (c) Make a copy of the headers for each address ...
> (d) Apply the special rewriting.
> (e) Do the deliveries with the special copy of the headers ...
> (f) If the message is deferred, save the one "main" copy ...
> (g) And other things I haven't thought of.
>
> All this is _massive_ redesign in the guts of Exim. Sufficient, I would
> think, to warrant calling it Exim2 or something. Consequently I am not
> at the moment very enthusiastic.
>
Well I can accept that. As I said a more general purpose model is
required.
Such that a Mail object would have an orginal sub-objects for the
envelope,
header, and main body. If the main body is treated as an object maybe
built
in support for MIME etc could be added at a latter date with less
problmes.
Anyway that aside the idea of such an Mail object is for it to be able
to
sporn children which only include those sub-objects that have been
altererd.
Such sporned children would be created by drivers during prcoessing of
the
orginal mail object. Then issues such as optional re-routing/directing
can also be flagged in Mail objects to determine if a child mail object
should
be save in queue along with the parent or left to be re-generated next
time
the orinal mail is re-processed.
I concied this is an item for Exim 3.00 not Exim 2.00 but you may have a
brain storm so its worth discussing now *8-)
--Sean
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