From owner-freebsd-hackers@FreeBSD.ORG  Tue Jan 25 14:32:41 2005
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Date: Tue, 25 Jan 2005 14:33:50 +0000
From: Bruce M Simpson <bms@spc.org>
To: DJF <deiif@yahoo.com>
Message-ID: <20050125143350.GI47638@dhcp120.icir.org>
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References: <20050125094646.GA969@nexus.hta.fhz.ch>
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cc: freebsd-hackers@freebsd.org
Subject: Re: Rawsock bpf mambo jambo?
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On Tue, Jan 25, 2005 at 10:46:47AM +0100, DJF wrote:
> What's the advantage in using the rawsock bpf combination instead of
> bpf (or raw socket) only?

Raw IP sockets for write take care of the following for you:
1) Computing IP checksums.
2) Inserting IP options.

BPF does neither of those things. For a while BPF was read-only, but it
has been read-write capable for quite some time.

BMS