Where to hook balsa filtering

[Emmanuel <e allaud wanadoo fr>]

	Hi all,
I'm almost done with filters implementations (not complete, not very
polished, specially UI, but usable). But before I put out patches it lacks
a central feature : actual filtering :) I have coded all functions to apply
filters, but I don't know where I could plug that in balsa fetch code (for
the moment I only plan to filter upon receiving).
For now I'm still using 1.1.7.
Thanks for any answer, I hope to put out patches as soon as possible (this
time I managed to test them a lot, so that they compile :) and run pretty
well, in fact I have no crash (still I think someone with a bit of effort
could manage to crash it)).
Bye
Manu