David Bremner <david@tethera.net> wrote:
> Edward Betts <edward@4angle.com> writes:
> > I wonder if 'notmuch insert' could be modified to detect and drop the From_
> > line before writing the message to disk and index it. It could do that
> > silently or with a warning.
> 
> I don't know about the larger question(s), but I'd suggest just escaping
> it to something like X-Envelope-From: . There may even be some
> semi-standard header to use for this.

The main piece of information in the From_ line is the return path address, a
properly configured MTA will add a Return-path header.

RFC 2821 says the Return-path header is added to a message "when the
delivery SMTP server makes the final delivery".

I don't think the From_ line needs to be captured into an X-Envelope-From
header.  We could make 'notmuch insert' add the 'Return-path' header to
messages if it is missing, but the From_ line is present. This is probably too
much complexity.

-- 
Edward.