From owner-freebsd-arch@FreeBSD.ORG  Mon Jun  5 15:43:48 2006
Return-Path: <owner-freebsd-arch@FreeBSD.ORG>
X-Original-To: freebsd-arch@freebsd.org
Delivered-To: freebsd-arch@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 4804116A51F;
	Mon,  5 Jun 2006 15:43:48 +0000 (UTC)
	(envelope-from ssouhlal@FreeBSD.org)
Received: from elvis.mu.org (elvis.mu.org [192.203.228.196])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 07C4B43D45;
	Mon,  5 Jun 2006 15:43:47 +0000 (GMT)
	(envelope-from ssouhlal@FreeBSD.org)
Received: from [172.30.10.163] (unknown [216.239.55.7])
	by elvis.mu.org (Postfix) with ESMTP id C87BD1A4D86;
	Mon,  5 Jun 2006 08:43:46 -0700 (PDT)
Message-ID: <448450FD.4030709@FreeBSD.org>
Date: Mon, 05 Jun 2006 17:42:53 +0200
From: Suleiman Souhlal <ssouhlal@FreeBSD.org>
User-Agent: Mozilla Thunderbird 1.0.7 (X11/20051204)
X-Accept-Language: en-us, en
MIME-Version: 1.0
To: Robert Watson <rwatson@FreeBSD.org>
References: <1fa17f810606050044k2847e4a2i150eb934ed84006f@mail.gmail.com>
	<Pine.GSO.4.64.0606050744190.13542@sea.ntplx.net>	<1fa17f810606050608l5bd2ec5ch37663375f6fa5b64@mail.gmail.com>	<Pine.GSO.4.64.0606051118180.14745@sea.ntplx.net>
	<20060605163559.N50057@fledge.watson.org>
In-Reply-To: <20060605163559.N50057@fledge.watson.org>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Cc: Daniel Eischen <deischen@freebsd.org>, MingyanGuo <guomingyan@gmail.com>,
	delphij@gmail.com, freebsd-arch@freebsd.org
Subject: Re: Why use `thread' as an argument of Syscalls?
X-BeenThere: freebsd-arch@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Discussion related to FreeBSD architecture <freebsd-arch.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-arch>,
	<mailto:freebsd-arch-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-arch>
List-Post: <mailto:freebsd-arch@freebsd.org>
List-Help: <mailto:freebsd-arch-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-arch>,
	<mailto:freebsd-arch-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Mon, 05 Jun 2006 15:43:55 -0000

Robert Watson wrote:
> 
> On Mon, 5 Jun 2006, Daniel Eischen wrote:
> 
>>> They are the same questions, I think ;-). Now would you please 
>>> explain "why use `proc' as an argument of Syscalls"  to me :)?  I've 
>>> read some source code of the kernel, but no comments about it found.
>>
>>
>> I don't know.  Convention?  It makes sense to me.
> 
> 
> Certainly consistency.  Most system calls do actually use the argument 
> at some point -- be it to look up a file descriptor, access control, or 
> the like, and the calling context has it for free and in-hand anyway.

But couldn't they just use curthread/curproc?

-- Suleiman