> I know there's no standard header for storing the envelope recipients for > a message (for good reason, especially when it comes to Bccs) but there > are times when it's useful. > > Does anyone know of a system that does that? I'm stashing them in > "X-Rcpt-To" at the moment, for lack of anything better, but if there's > even a marginal ad-hoc standard for it I'd like to be consistent.
Original-Recipient looks like the most standard approach. https://tools.ietf.org/html/rfc3798#section-2.3 2.3. The Original-Recipient Header Since electronic mail addresses may be rewritten while the message is in transit, it is useful for the original recipient address to be made available by the delivering MTA. The delivering MTA may be able to obtain this information from the ORCPT parameter of the SMTP RCPT TO command, as defined in [RFC-SMTP] and [RFC-DSN-SMTP]. [RFC-DSN-SMTP] is amended as follows: If the ORCPT information is available, the delivering MTA SHOULD insert an Original-Recipient header at the beginning of the message (along with the Return-Path header). The delivering MTA MAY delete any other Original-Recipient headers that occur in the message. The syntax of this header is as follows: original-recipient-header = "Original-Recipient" ":" address-type ";" generic-address The address-type and generic-address token are as specified in the description of the Original-Recipient field in section 3.2.3. The purpose of carrying the original recipient information and returning it in the MDN is to permit automatic correlation of MDNs with the original message on a per-recipient basis. -- Rob Mueller r...@fastmail.fm _______________________________________________ mailop mailing list mailop@mailop.org https://chilli.nosignal.org/cgi-bin/mailman/listinfo/mailop
