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Date: Fri, 24 Sep 2004 15:23:21 +1000
From: Phillip Crumpler <listsubs@crippy.mel.crumpler.com.au>
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Subject: ifunit and struct ifnet/ieee80211com
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Hi hackers,

A few questions re. ifunit and struct ifnet/ieee80211com, if anyone can 
help me out:

I assume that for a wireless interface ifunit will return a pointer to a 
struct ieee80211com. Is there any way to tell which of these I have, so 
I don't try to access ieee80211com members in a struct that is actually 
the smaller infet? Both ethernet and wireless ethernet seem to use 
if_type == 6 (IFT_ETHER) and if_physical == 0. Can I distinguish which 
type I have or should I just make sure I know beforehand?

Also, what is the lifetime of the (struct ifnet *) that ifunit returns? 
If an interface goes away is the ifnet freed, leaving me with a dangling 
pointer, or is it kept but marked inactive in some way?

cheers,

Phillip