device filtering support

[Michael Plante]

Pete Batard wrote:
>> At this stage we should be able to have a threaded solution that
>> does the querying we need once per app.

Are you saying this will not work? ... see next point for why I think you
MIGHT be saying that...


>> - Travis indicated that he sees querying hubs as unacceptable, even if
>> we do it once per app, as it could come pollute transfers from
>> existing ones. The only solution I see to meet his request then is to
>> have a separate process.

If hubs becoming corrupted is why threading won't work, then we're dead in
the water.  I hate to break it to you, but libusbx is not the only game in
town.  There is also proprietary software, as well as openusb or whatever
it's called (I ignore those messages frankly).  And maybe libusb will copy
your code too.  So I hope I'm misunderstanding and that you're merely trying
to optimize, rather than saying that threading won't work at all.



I'm actually really not all that concerned about hotplug or filtering right
now; my concern is more long term and basic.  Here's my real point, which I
wasn't clear enough about.  Say you have five horribly buggy libusbx-using
programs on the system written by 5 developers.  We make libusbx perfectly
clean, which is a chore unto itself.  That's not good enough.  I want those
programs as isolated as possible, so when each dies its fiery death, it
doesn't take the others down with it at the same time.  Introducing shared
resources and that kind of thing is bad -- we moved away from that when we
ditched 3.1/9x, to speak loosely.  And while I said I'd try to offer time to
help with integration, I didn't say I have time to help with a whole new
interprocess communication design, which I forsee as being something of a
whole new nightmare, if it's even possible to do right.

Regards,
Michael