Kurt Hackenberg wrote in <[email protected]>: |On Sun, Aug 24, 2025 at 02:44:35AM +0200, Steffen Nurpmeso wrote: | |>I just stumbled over the fact that mutt turns |> |> From MAILER-DAEMON-nono-0 Wed Oct 2 01:50:07 1996 |> |> This is a body, but not a valid message |> |>(multiply .. or so .. to create a mulit-member mbox) |>into a "valid" message. | |Sounds like your testing has found that Mutt accepts a zero-length |message header section, at least from an mbox file. I haven't read the |Mutt code that does that; I agree that's not valid RFC 822, and Mutt |probably shouldn't accept it. | |>Thing is that RFC 4155 is lala... | |Correct. That RFC should be ignored.
Mumble mumble!!! It defines the MBOX DB format. |>but for example qmail-mbox from ~1996 |> [curl -I http://qmail.org./man/man5/mbox.html | |That's good documentation, but incomplete. The syntax of mbox From_ |lines varies more than that, and it doesn't mention the Berkeley mbox |variant or the mbox header Lines:. | |More mbox documentation: | |Library of Congress: |<https://www.loc.gov/preservation/digital/formats/fdd/fdd000383.shtml> |Jonathan de Boyne Pollard, 2004: |<https://web.archive.org/web/20161023162432/jdebp.eu/FGA/mail-mbox-forma\ |ts.html> | |Both of those are good, but neither documents the Berkeley variant or |the header Lines:. | |Jamie Zawinski, 1996: |<https://www.jwz.org/doc/content-length.html> |Names and describes BSD (Berkeley) mbox, but doesn't mention that, in |that variant, message "From " lines are only escaped with '>' after |blank lines. Didn't he say he dislikes those. My MUA ignores them ;) |Here's something I wrote about mbox: |<http://www.panix.com/~kh/mailstorage/mbox_is_bad.html> I love MBOX. Hhmm, i do not agree with what you say, since for example Return-Path: and Received: are real RFC 5321 headers, which require line unfolding and extensive parsing, whereas the From_ line is always a single line that can be easily parsed. (With an easy template parser -- which of course is needed, but was developed in hmm i have forgotten, before 1995 anyhow.) And there are clear variants, MBOXO, MBOXRD, it is only the question which is used when ;), and all that. Like you say. No, i love MBOX, the thing is that this MBOX quoting of all kind is unnecessary if the messages are MIME encoded, *if* the MIME encoding takes care for ^'From ', which i think practically all do. So, for almost thirty years, hmhm, MBOX is fine out. So RFC 4155 is a great database format in conjunction with MIME encoded emails, especially for long time storage of constant data; or for "normal" emails and append-only. Completely unambiguous. Thing is pretty clearly, and you do not mention this at all, that it must be a RFC 822 message. Actually Dr. Werner Fink (SuSE) prodded me repeatedly years ago to improve the MBOX parsing of the MUA i maintain, in order to comply with that. Now i stand here, but the rest stands there ;), and i consider to undo that detection, since it will give different results to all the others. Having said that, whatever standard, they all say that there must be a completely empty line before the From_ line, and note that mutt does start a new message for that very very evil email that they all got wrong (including my one, which ended up saying something like "missing multipart boundary", and not allowing normal view at all, only Showing of the complete, raw message) though you dropped that quote. This should possibly be reconsidered. *Or* i should also reconsider, like i said, to "hotten" From_ detection even then. |>I have to rewrite "my thing"... |... |>(I am about to add MIME boundary search mode instead of From_ |>search if we have a MIME message... | |That might help some. | |If your thing attempts to read all variants of mbox, it probably should |also pay attention to the mbox length headers Lines: and |Content-Length:. Don't trust them completely, though; sometimes they're \ |wrong. No we drop them now (for a decade or so). And i will not readd those, they are a misconception; i think Zawinski agreed with that, but i have not reread his statements now. --End of <[email protected]> --steffen | |Der Kragenbaer, The moon bear, |der holt sich munter he cheerfully and one by one |einen nach dem anderen runter wa.ks himself off |(By Robert Gernhardt)
