Re: That newfangled IMAP thing...

[Matthias Andree <matthias.andree@gmx.de>]

Am 07.09.2010 16:52, schrieb Richard Riley:
> Wes Hardaker <wes@hardakers.net> writes:
> 
>>>>>>> On Sun, 05 Sep 2010 13:20:27 +0200, Lars Magne Ingebrigtsen <larsi@gnus.org> said:
>>
>>>> Split incoming mail with procmail, or sieve, or the mail splitting tool
>>>> of your choice, directly into the imap server's folders.
>>
>> LMI> Yuck.  On the mail server?  Do people set up procmail rules still, in
>> LMI> this day and age?
>>
>> Procmail sucks (and needs to be rewritten).
> 
> What sucks about procmail? It's used throughout the world and heartily
> recommended by many. Certainly my (admittedly minor) use of it suggested
> it was very competent, reliable and easy to use.

Recommendations don't count, because you usually don't get scientific
recommendations, people will stop their search on the first tool that does the
job on initial testing and stick with it, without looking further if there's
better stuff.  Only later, long after they've sold their souls and mail, will
they notice if something goes wrong.


Procmail is anything, but not easy to use or reliable or maintained.
It's been abandonware for nearly a decade.

In .procmailrc, you need to write all the error handling yourself because
procmail will happily try the next recipe if the previous failed to deliver.
Thus, if you want to avoid mail ending up in the wrong box, you'd better be
spamming the whole procmailrc with

:0e
{
  EXITCODE=75
  HOST
}

after each and every delivering recipe.  And I've seen procmail exit with
non-/usr/include/sysexits.h error codes more often than I cared to count, and
I've seen procmail-induced inadvertent non-delivery notices (aka. bounce mail)
far more often than I care to remember.


Compare that with maildrop that automatically defers mail on write errors, and
has a rather intuitive syntax, here a snippet from my $HOME/.mailfilter

# ...
# check upstream's spam scanner status first
if (/^X-Spam-Status: Yes/)
        to "Mail/spam1"

xfilter "bogofilter -e -p -l"

if (/^X-Bogosity: Spam, tests=bogofilter/)
  to "Mail/spam-bf"

if (/^X-Bogosity: Unsure, tests=bogofilter/)
  cc "Mail/unsure"

# LBDB support
`/usr/bin/env lbdb-fetchaddr -d "%Y-%m-%d"`
# ...


Getting that right in procmail takes three screenfuls of text.

-- 
Matthias Andree