Subject: Re: adding an 802.11 data link type
To: None <email@example.com>
From: Atsushi Onoe <firstname.lastname@example.org>
Date: 08/08/2002 10:19:11
Content-Type: Text/Plain; charset=us-ascii
> So if I understand your code right, (ic->ic_rawbpf) is a necessary but not
> sufficient condition to hand the packet off to bpf_mtap. The bpf system
> would have had to ask for that packet type too. So something like:
> if ((ic->ic_rawbpf) && (ic->ic_raw_bpfcount))
> bpf_mtap(ic->ic_rawbpf, m0);
Please note that this interface is very similar to existing bpf hook.
So the value of ic->ic_rawbpf remains NULL unless someone issues BPFSETIF
and BIOCSDLT, and recovered to NULL when the bpf listener closes bpf.
The number of opening listeners are counted in bpf itself.