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Date: Sun, 24 Feb 2002 10:18:39 -0800 (PST)
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To: net@freebsd.org
From: John Polstra <jdp@polstra.com>
Cc: ras@e-gerbil.net
Subject: Re: incorrect checksums with xl?
In-Reply-To: <20020222205853.GC413@overlord.e-gerbil.net>
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In article <20020222205853.GC413@overlord.e-gerbil.net>,
Richard A Steenbergen  <ras@e-gerbil.net> wrote:
> On Fri, Feb 22, 2002 at 09:43:58AM -0800, John Polstra wrote:
> > Remember, bpf is used by many things besides tcpdump.  Adding these
> > flags would require extending the bpf API.  They couldn't be added for
> > the default case, because that would break compatibility with other
> > applications.  They'd have to be enabled specifically, by means of a
> > new ioctl.
> 
> You could always just add a flags field to struct bpf_hdr, and hope noone 
> is stupid enough to hardcode the size.

That would break binary compatibility.  Think about third-party
applications, not available in source form, which people paid money
for.  They would suddenly stop working.

John
-- 
  John Polstra
  John D. Polstra & Co., Inc.                        Seattle, Washington USA
  "Disappointment is a good sign of basic intelligence."  -- Chögyam Trungpa


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