locking w/ whitelisting

[David Relson]

At 08:52 PM 3/25/03, Barry Gould wrote:

>Hi David,
>
>I'm not really worried about corruption (I understand bogofilter locks well.)
>
>Actually, I was worried that procmail might launch both bogofilter threads 
>at once, since I'm using the copy (c) directive in procmail to make a copy 
>and process it.
>In which case, the bogofilter -n might not be done before the other 
>bogofilter started, causing the whitelisting to be ignored _for the 
>current message_.
>i.e., a possible false positive.
>
>Maybe I'm wrong? (does procmail parallelize or run everything serially? 
>IIRC, it will parallelize when it doesn't need to wait for the result of 
>something.)

Barry,

Serialize or parallellize?  Sounds like a question for a procmail mailing list.

You could have procmail apply a procmail lock when running 
bogofilter.  Roughly something like:

:0c:/tmp/bogofilter.lock
...whitelist
bogofilter -n

:0:/tmp/bogofilter.loc
bogofilter -p -e

Guaranteeing that "bogofilter -n" is done before "bogofilter -p -e" doesn't 
prevent false positives.  Remember that bogofilter uses token count ratios 
in its scoring.  If a whitelisted user sends the "Hey Barry, look at this 
quintuple-X p0rno sp4m I got", the message may well be rated spam.  If you 
want a whitelist match to skip the spam classification, you need something 
like:

:0
* ? whitelist
{
    :0c
    | bogofiltere -n
}
:0E
| bogofilter -p -e

This is a rough approx of what's needed.  See file 
contrib/procmailrc.example for real code.

David