Subject: Re: [PATCH v7 2/2] send-email: expose header information to git-send-email's sendemail-validate hook

From: Junio C Hamano <[email-masked]>
Date: Tue, 17 Jan 2023 08:00:42 -0800

"Strawbridge, Michael" <[email-masked]> writes:

> +This hook is invoked by linkgit:git-send-email[1].
> +
> +It takes these command line arguments. They are,
> +1. the name of the file which holds the contents of the email to be sent.
> +2. The name of the file which holds the SMTP envelope and headers of the email.

The previous iteration said SMTP headers, but now this talks about
envelope.  I however did not think we have direct access to any
envelope information [*] (i.e. such a feature is necessary if we
want to send to one set of recipients by specifying their addresses
in the envelope, while recording different set of recipients to the
e-mail headers' To: and Cc: list)?

	Side note.  We can specify different sender and it gets
	passed as a command line argument "-f $sender" to the
	sendmail program, which is used in "MAIL FROM" SMTP
	envelope.  But I do not think we muck with the list of
	recipients that appear in the header when we formulate "RCPT
	TO".  And I do not see where you give "MAIL FROM" value in
	the input to the hook in the patch.

If we say "we will give your hook information in the envelope and
headers" to those who know the distinction between the two, they
will inevitably say "that is great. Now how do I tell which in file
$2 are in the envelope and which are in the header, when some of
them are different?"

We just hand the message plus the header, and let $sendmail_cmd come
up with the envelope info using what is in the header, no?  I am not
sure we want to mention envelope as that would give readers a false
impression that we may treat it separately from the headers.

Thanks.