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Date: Wed, 7 Sep 2011 07:05:42 +0200
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From: "K. Macy" <kmacy@freebsd.org>
To: Arnaud Lacombe <lacombar@gmail.com>
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Cc: freebsd-net@freebsd.org, Adrian Chadd <adrian@freebsd.org>,
	Doug Barton <dougb@freebsd.org>
Subject: Re: No IPFW binary compat across versions ?
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On Wed, Sep 7, 2011 at 6:16 AM, Arnaud Lacombe <lacombar@gmail.com> wrote:
> Hi,
>
> On Mon, Sep 5, 2011 at 8:45 PM, Doug Barton <dougb@freebsd.org> wrote:
>> On 09/05/2011 17:18, Arnaud Lacombe wrote:
>>> From my point of view, I should be able to run a FreeBSD 9.0 kernel
>>> (when released) on top of a FreeBSD 5 userland without such issues.
>>
>> Unfortunately your expectation is completely unrealistic.
>>
> Completely unrealistic ? Seriously, you've got to be kidding me ?
>
> I just downloaded a 4 (_four_) years old OpenWRT image, built the
> latest Linux kernel in development and it worked just fine. netstat(8)
> works just fine, I can pick a random iptables tutorial on the net, and
> it still works fine. Those binaries are 4 years old and still work, oh
> and I can go back at will to the original 2.6.19 without issue.
>

Interesting. I remember binaries routinely breaking with minor glibc
changes, such that in the linux community it was accepted that dynamic
linking was "a bad thing". However, it is entirely possible that
they've grown up in the mean time while we've stood still.