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To: <linux-kernel@vger.kernel.org>
Subject: Re: Generic HDLC interface continued
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From: Krzysztof Halasa <khc@pm.waw.pl>
Date: 02 Oct 2002 00:09:33 +0200
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Francois Romieu <romieu@cogenit.fr> writes:

> Ok, the 'type' attribute isn't enough.
> 
> I feel like we are trying to do two things at the same time:
> a) the size of the allocated area isn't required if we need to do something
>    real with the data: if size doesn't match what is expected, we loose 
>    anyway
> b) if we don't care about the copied data, we actually ask for the subtype
>    of the interface
> 
> -> a) and b) are two different operations imho.

Depends on the point of view, but generally it might be true.
However, it is quite practical to do a+b in one call:
- utilities will always do it in exactly that order,
- we don't need to worry about races (process A gets type/size; process
  B changes protocol; process A gets invalid data).
-- 
Krzysztof Halasa
Network Administrator