From owner-freebsd-hackers  Sat Dec 21  9:47:25 2002
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Date: Sat, 21 Dec 2002 09:45:54 -0800
From: Terry Lambert <tlambert2@mindspring.com>
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To: Pawel Jakub Dawidek <nick@garage.freebsd.pl>
Cc: freebsd-hackers@freebsd.org
Subject: Re: Syscall number.
References: <20021220184337.GD11475@garage.freebsd.pl> <20021221032233.GG11475@garage.freebsd.pl>
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Pawel Jakub Dawidek wrote:
> On Fri, Dec 20, 2002 at 07:43:37PM +0100, Pawel Jakub Dawidek wrote:
> +> Simple example (from kld module):
> +>
> +> sysent[SYS_chmod].sy_call = myfunction;
> +> sysent[SYS_open].sy_call = myfunction;
> +> sysent[SYS_execve].sy_call = myfunction;
[ ... ]
> Ok, I've found solution (ripped from trap.c, ehh).

This is actually a bad way to do things.

There is a system call loadable module type, and you should
use that instead of directly accessing the system call entry
table and stomping on values without asserting appropriate
locks.

-- Terry

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