From owner-freebsd-usb@FreeBSD.ORG  Thu Aug 17 13:34:45 2006
Return-Path: <owner-freebsd-usb@FreeBSD.ORG>
X-Original-To: freebsd-usb@freebsd.org
Delivered-To: freebsd-usb@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 7E8AD16A4E0
	for <freebsd-usb@freebsd.org>; Thu, 17 Aug 2006 13:34:45 +0000 (UTC)
	(envelope-from hselasky@c2i.net)
Received: from swip.net (mailfe01.swip.net [212.247.154.1])
	by mx1.FreeBSD.org (Postfix) with ESMTP id B1EDA43D53
	for <freebsd-usb@freebsd.org>; Thu, 17 Aug 2006 13:34:44 +0000 (GMT)
	(envelope-from hselasky@c2i.net)
X-T2-Posting-ID: gvlK0tOCzrqh9CPROFOFPw==
X-Cloudmark-Score: 0.000000 []
Received: from [193.216.86.144] (HELO [10.0.0.249])
	by mailfe01.swip.net (CommuniGate Pro SMTP 5.0.8)
	with ESMTP id 236422158; Thu, 17 Aug 2006 15:34:42 +0200
From: Hans Petter Selasky <hselasky@c2i.net>
To: freebsd-usb@freebsd.org,
 tofik@oxygen.az
Date: Thu, 17 Aug 2006 15:34:51 +0200
User-Agent: KMail/1.7
References: <35069.85.132.32.38.1155816624.squirrel@85.132.32.38>
	<20060817121307.GA804@gremlin.foo.is>
	<35146.85.132.32.38.1155817977.squirrel@85.132.32.38>
In-Reply-To: <35146.85.132.32.38.1155817977.squirrel@85.132.32.38>
MIME-Version: 1.0
Content-Type: text/plain;
  charset="utf-8"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline
Message-Id: <200608171534.53213.hselasky@c2i.net>
Cc: 
Subject: Re: USB_ATTACH_SETUP macros question
X-BeenThere: freebsd-usb@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: FreeBSD support for USB <freebsd-usb.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-usb>,
	<mailto:freebsd-usb-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-usb>
List-Post: <mailto:freebsd-usb@freebsd.org>
List-Help: <mailto:freebsd-usb-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-usb>,
	<mailto:freebsd-usb-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 17 Aug 2006 13:34:45 -0000


>
> Made a little test which shows that this code is going to be executed only
> once.How did i miss that :) Now the other question comes next:
> Why don not we use just:
> #define USB_ATTACH_SETUP \
> sc->sc_dev = self; \
> device_set_desc_copy(self, devinfo); \
> device_printf(self, "%s\n", devinfo);

Because that is dangerous.

Consider the following:

if (1) USB_ATTACH_SETUP;

What is the meaning of the statement above?

What is going to get executed?

--HPS