Subject: Re: Filtering in Monitor Mode (was Question about PRISM2  header rate field)
From: Johannes Berg <johannes@sipsolutions.net>
To: Andy Green <andy@warmcat.com>
Cc: Michael Wu <flamingice@sourmilk.net>,
	linux-wireless@vger.kernel.org
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Date: Mon, 05 Mar 2007 14:22:37 +0100
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On Mon, 2007-03-05 at 13:18 +0000, Andy Green wrote:

> Not sure I explained well enough: looking at libpcap sources, it=20
> compiles the filter you request into a bytecode and then gives it to the=20
> kernelside using an ioctl.  When you recv() or select() on the monitor=20
> interface after that, you block until something matching your filter=20
> definition turns up.  Userspace doesn't hear about the rest of it.

Uh eh right, I'm confused :)

The power save mode argument still holds though, we might address that
with non-promisc monitor interfaces even though they do have a couple of
problems (you need to be associated on a different virtual netdev for it
to make sense...)

johannes

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