bug#6574: 24.0.50; Rmail 23 uses a broken mailbox format (mboxo) instead of a sane one like mboxrd

[Glenn Morris]

Version: 24.4

Mark Lillibridge wrote:

>     Examining unrmail.el from Gnu emacs 24.0.50.1 (lines 228-231):
>
>           ;; ``Quote'' "\nFrom " as "\n>From "
>           ;;  (note that this isn't really quoting, as there is no requirement
>           ;;   that "\n[>]+From " be quoted in the same transparent way.)
>
> clearly shows that Rmail 23 is using the mboxo format.  

Unrmail has used mboxo when converting from Babyl to mbox since forever;
it's not something new that appeared in 23. I think the lack of comments
over the years indicates this is not a big deal.

However, I agree that mboxrd is better so I made unrmail default to
that, with an option unrmail-mbox-format that you can set to mboxo or
mboxrd.

Rmail itself (as opposed to unrmail) does not care about mboxo or
mboxrd, with the exception of the display of non-MIME messages.
I added a similar option rmail-mbox-format for that.

(http://debbugs.gnu.org/9841 remains as a separate issue at this time)