Subject: Re: where do system calls from userland start
To: Hubert Feyrer <hubert@feyrer.de>
From: Travis H. <solinym@gmail.com>
List: tech-kern
Date: 08/24/2006 22:49:41
On 8/24/06, Hubert Feyrer <hubert@feyrer.de> wrote:
> > Also, I recall reading about NT internals versus Unix, and someone
> > mentioned that if you wanted to add a new system call or change the
> > meaning of an argument or add an argument, that you got a lot of
> > resistance in Unix.  I'm sure there was a good reason, so why exactly
> > is that the case?  Does NT have a technical advantage in the way it
> > handles system calls?
>
> Well what will all the applications do that expect the old behaviour?

Well, if you're adding a syscall, few apps will rely on an undefined
syscall staying undefined.   For modifying an extant system call, it
could check to see how many arguments are on the stack and branching
appropriately, even though it's ugly.
-- 
"If you're not part of the solution, you're part of the precipitate."
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