Re: [Nmh-workers] [patch] filtering support for inc

[Jon Steinhart]

Ken Hornstein writes:
> >Well, I seem to recall that there was documentation :-)  My recollection is
> >that there are 3 hooks, add, delete, and refile.  And as I said earlier, they
> >could certainly be made more robust.  Maybe it's time to start a discussion.
> >>From my perspective, what I need is to know what messages exist by folder 
> >>and
> >message number.  My use case was to have an external database associated with
> >the mh database.  What do other people want?
> 
> Sigh. I think we're talking past each other.
> 
> People asked, "What can we do about message filtering?"
> 
> You said, "Hey, check out my hooks support".
> 
> My response ... and perhaps I didn't make this very clear ... is that I
> do not think the hooks support is suitable at all for message filtering.
> By "message filtering" I mean (and I think everyone else means), storing
> messages in particular folders based on some criteria.  I am pretty sure
> the hooks support CANNOT do that, because there's no way for a hook to tell
> the upper level "Please move this message to folder <X>", and I have a
> suspicion that if you tried to move a message IN a hook, you'd either get
> a deadlock because of sequence file locking, or the various programs that
> call hooks would get unhappy.  This is what I was alluding to when I said
> there was a lack of documentation; maybe, Jon, in your mind you never
> intended anyone to move messages from inside hooks, because that wasn't
> your intended usage.
> 
> If the goal is to filter messages at "inc" time, then I'd guess that the
> best thing to do would be to add a new interface that allowed you to tell
> "inc" where you wanted the message to end up.
> 
> --Ken

Well yeah, now that filtering is defined in this way it is not something that
the hooks support or were ever intended to support.  I do this sort of
filtering with a sendmail milter but that's not a solution for the 
faint-hearted.

Jon