No IPFW binary compat across versions ?

[Julian Elischer]

On 9/5/11 2:44 PM, Arnaud Lacombe wrote:
> Hi,
>
> On Mon, Sep 5, 2011 at 4:18 PM, Arnaud Lacombe<lacombar at gmail.com>  wrote:
>> Hi,
>>
>> On Mon, Sep 5, 2011 at 3:14 PM, K. Macy<kmacy at freebsd.org>  wrote:
>>> -STABLE only implies that the ABI does not change during that release
>>> line. It makes no guarantees when moving from one branch to the next.
>>>
>> IIUC, FreeBSD does not provide binary backward compatibility between
>> version at all, is that it ?
>>
> I guess the answer is "NO", on the same system:
>
> # netstat -m
> netstat: memstat_mtl_find: zone mbuf_jumbo_pagesize not found
>
> It would seem that COMPAT_FREEBSD7 is just as useful as is eyes powder
> on a scare-crow...
>
>   - Arnaud
>

That is not quite correct.

WE do not guarantee interfaces that are used for system configuration etc.

Interfaces used in normal data processing applications we try very 
hard to keep stable,
It is assumed that applications that use the system administration 
interfaces will come with the system.

for example I can run a "make world" in a chroot populated with 
freebsd 1.1 and it actually works (after a few minor tweeks)
(actually I last tested this at 8.1 ).. required a change of PID_MAX 
in the kernel config file and a.out compatibility