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+ Sun, 19 Jul 2015 01:22:15 -0700 (PDT)\r
+From: Mark Walters <markwalters1009@gmail.com>\r
+To: David Bremner <david@tethera.net>, mailinglists@nawaz.org,\r
+ notmuch@notmuchmail.org\r
+Subject: Re: Modify message after send...?\r
+In-Reply-To: <87a8uswpan.fsf@maritornes.cs.unb.ca>\r
+References: <878uacpwse.fsf@fester.com> <87a8uswpan.fsf@maritornes.cs.unb.ca>\r
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+Date: Sun, 19 Jul 2015 09:22:14 +0100\r
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+\r
+\r
+>> BTW, all I really want to do is modify the From: field based on the\r
+>> recipients (for every email, with no default From). I'll welcome\r
+>> suggestions for existing ways to do that. I Googled a little, but didn't\r
+>> find a clear good solution. Furthermore, I expect over time the rules by\r
+>> which I pick the From: field will get more complex than my knowledge of\r
+>> Elisp.\r
+\r
+I don't know how practical the following is but an alternative which\r
+would keep you entirely outside lisp would be to configure\r
+sendmail-program to be your python script and let it modify the message\r
+and then send it on to whatever sendmail program you use.\r
+\r
+Getting everything right with command line arguments and the message on\r
+stdin (I guess) and keeping any sane form of error handling may be difficult \r
+\r
+Also, note that sendmail-program is not notmuch specific so if you\r
+configure it might affect other emacs mail stuff like gnus.\r
+\r
+Best wishes\r
+\r
+Mark\r
+\r
+\r
+\r