Modify message after send...?

[mailinglists at nawaz.org]

Hi,

I use notmuch via Emacs.

Here's what I want:

When I hit C-c C-c to send a message, I'd like it to be passed to a
script (likely a Python one, although I may consider an Elisp function
if an external script is not possible) for modification of headers,
before it is sent to the MTA (Postfix in my case). A bonus would be to
have the modified message stored in the FCC location, instead of the
original one.

Is this possible? An alternative may be to modify the message /before/
it goes to message-send-and-exit. I'm inexperienced in Elisp - would
this be via what's called "advising"?

BTW, all I really want to do is modify the From: field based on the
recipients (for every email, with no default From). I'll welcome
suggestions for existing ways to do that. I Googled a little, but didn't
find a clear good solution. Furthermore, I expect over time the rules by
which I pick the From: field will get more complex than my knowledge of
Elisp.

Thanks.

-- 
My sister opened a computer store in Hawaii. She sells C shells down by
the seashore.


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