From owner-freebsd-hackers@FreeBSD.ORG  Thu Aug 11 21:16:13 2005
Return-Path: <owner-freebsd-hackers@FreeBSD.ORG>
X-Original-To: freebsd-hackers@freebsd.org
Delivered-To: freebsd-hackers@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 6F4D816A41F
	for <freebsd-hackers@freebsd.org>; Thu, 11 Aug 2005 21:16:13 +0000 (GMT)
	(envelope-from julian@elischer.org)
Received: from delight.idiom.com (delight.idiom.com [216.240.32.16])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 2C74843D45
	for <freebsd-hackers@freebsd.org>; Thu, 11 Aug 2005 21:16:13 +0000 (GMT)
	(envelope-from julian@elischer.org)
Received: from idiom.com (idiom.com [216.240.32.1])
	by delight.idiom.com (Postfix) with ESMTP id 0E7421F7CED;
	Thu, 11 Aug 2005 14:16:13 -0700 (PDT)
Received: from [192.168.2.2] (home.elischer.org [216.240.48.38])
	by idiom.com (8.12.11/8.12.11) with ESMTP id j7BLGAc2075519;
	Thu, 11 Aug 2005 14:16:12 -0700 (PDT)
	(envelope-from julian@elischer.org)
Message-ID: <42FBC017.6050000@elischer.org>
Date: Thu, 11 Aug 2005 14:16:07 -0700
From: Julian Elischer <julian@elischer.org>
User-Agent: Mozilla/5.0 (X11; U; FreeBSD i386; en-US; rv:1.7.7) Gecko/20050424
X-Accept-Language: en, hu
MIME-Version: 1.0
To: Dirk GOUDERS <gouders@et.bocholt.fh-ge.de>
References: <200508111813.j7BIDeFP055360@sora.hank.home>
In-Reply-To: <200508111813.j7BIDeFP055360@sora.hank.home>
Content-Type: text/plain; charset=us-ascii; format=flowed
Content-Transfer-Encoding: 7bit
Cc: freebsd-hackers@freebsd.org, Sergey Uvarov <uvarovsl@mail.pnpi.spb.ru>
Subject: Re: preferable way to control kernel module
X-BeenThere: freebsd-hackers@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Technical Discussions relating to FreeBSD
	<freebsd-hackers.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>, 
	<mailto:freebsd-hackers-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hackers>
List-Post: <mailto:freebsd-hackers@freebsd.org>
List-Help: <mailto:freebsd-hackers-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>,
	<mailto:freebsd-hackers-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 11 Aug 2005 21:16:13 -0000

Dirk GOUDERS wrote:
>  > >>Shouldn't that be no problem if he sets the offset parameter to
>  > >>SYSCALL_MODULE to NO_SYSCALL (get the next free offset)?
>  > > 
>  > > 
>  > > But then you have to communicate the syscall number out to your userland 
>  > > applications somehow, and the applications have to know how to invoke a 
>  > > syscall by hand (perhaps they could use the syscall() function, but still)


In the past, I've used a sysctl to communicate out the syscall number.

you only need to do the syscall once,
and it confirms to the program that the syscall is correctly installed.