From owner-freebsd-hackers@FreeBSD.ORG  Wed Apr 23 16:43:54 2008
Return-Path: <owner-freebsd-hackers@FreeBSD.ORG>
Delivered-To: hackers@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34])
	by hub.freebsd.org (Postfix) with ESMTP id 9C1BB1065680
	for <hackers@freebsd.org>; Wed, 23 Apr 2008 16:43:54 +0000 (UTC)
	(envelope-from mwm@mired.org)
Received: from mired.org (student.mired.org [66.92.153.77])
	by mx1.freebsd.org (Postfix) with ESMTP id 137F18FC1A
	for <hackers@freebsd.org>; Wed, 23 Apr 2008 16:43:53 +0000 (UTC)
	(envelope-from mwm@mired.org)
Received: (qmail 54751 invoked from network); 23 Apr 2008 12:42:33 -0400
Received: from unknown (HELO mbook-fbsd) (192.168.195.251)
	by 0 with SMTP; 23 Apr 2008 12:42:33 -0400
Date: Wed, 23 Apr 2008 12:43:51 -0400
From: Mike Meyer <mwm@mired.org>
To: Roman Divacky <rdivacky@freebsd.org>
Message-ID: <20080423124351.426627d3@mbook-fbsd>
In-Reply-To: <20080423162635.GA42593@freebsd.org>
References: <7d6fde3d0804222240j6b42b77yd86d8accb5a959fa@mail.gmail.com>
	<20080423025048.6b51a580@bhuda.mired.org>
	<5F412E73-29FC-4876-A6F0-9BC269876192@bitpowder.com>
	<20080423113951.020f0130@mbook-fbsd>
	<20080423162635.GA42593@freebsd.org>
Organization: Meyer Consulting
X-Mailer: Claws Mail 3.0.2 (GTK+ 2.12.5; amd64-portbld-freebsd7.0)
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
X-Mailman-Approved-At: Wed, 23 Apr 2008 17:44:09 +0000
Cc: Mike Meyer <mwm-keyword-freebsdhackers2.e313df@mired.org>,
	Garrett Cooper <yanefbsd@gmail.com>, hackers@freebsd.org
Subject: Re: strdup(NULL) supposed to create SIGSEGV?
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: Wed, 23 Apr 2008 16:43:54 -0000

On Wed, 23 Apr 2008 18:26:35 +0200 Roman Divacky <rdivacky@freebsd.org> wrote:

> > I think someone gave the reason I'm about to: trying to copy a NULL
> > pointer means I have a bug somewhere earlier in my code that will
> > eventually produce visibly wrong results - a segfault being such. The
> > sooner that happens after the bug, the less code I have to search to
> > find it, the better for me.
> 
> if only the fix was something else than
> 
> if (ptr != NULL)
>    strdup(ptr);
> 
> :)

Again, under what conditions would this "fix" be considered correct?
I.e. - when does it make sense to try and duplicate a string that
isn't?

	<mike

-- 
Mike Meyer <mwm@mired.org>		http://www.mired.org/consulting.html
Independent Network/Unix/Perforce consultant, email for more information.