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From: Marcel Moolenaar <marcel@xcllnt.net>
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Date: Fri, 17 Feb 2012 07:48:35 -0800
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To: Gleb Smirnoff <glebius@FreeBSD.org>
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Subject: Re: Abstracting struct ifnet
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On Feb 17, 2012, at 5:53 AM, Gleb Smirnoff wrote:
> M> Thoughts, feedback and suggestion are welcome,
> 
> Is it possible to make the structure the driver points to opaque?
> 
> Once made, that would allow us to hack on the ifnet (or on its
> successor - iflogical) more aggressively without breaking ABI/API.

Yes, that's the idea. Backward compatibility kinda conflicts
with making struct ifnet entirely abstract, but I don't see
that as a problem without solution. Only as a problem for
which an acceptable solution must be found.

For example: you can introduce a define that either old or
new drivers use to indicate whether they need full visibility
or whether an abstract type works. This then drives what is
defined/declared and how it's defined/declared.

-- 
Marcel Moolenaar
marcel@xcllnt.net