Re: [Exim] -t and Resent- header lines

On Thu, May 08, 2003 at 03:46:11PM +0100, Philip Hazel wrote:
> > My question to start with is this:
> > Why does Exim give up with -t if Resent- headers are present?
>
> Because I could not think of a simple way to figure out which was the
> "most recent" set, from which to extract the recipient addresses.

Each new set of resent fields is prepended to the message;
that is, the most recent set of resent fields appear earlier in the
message.

So, we know that the top most headers are from the most recent resend.
The only problem is that we don't know where duplicate Resent- headers
overlap. For example:
Resent-From: Foo
Resent-To: Bar
Resent-Date: something
Resent-From: Another
Resent-To: morefoo
Resent=Date: bazaa

That's easy to seperate: Look at each header parsed. The first time a
reader name is repeated, you're looking at a new set of headers.

It doesn't hold true for EVERY circumstance, but surely it must we any
MUA out today. I don't know anything that munges it that badly. RFC2822
needs to be clearer, and should require a seperator between blocks as it
does for Trace fields.