From owner-freebsd-hackers@FreeBSD.ORG  Thu Apr 24 07:22:52 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 49DBF1065673
	for <hackers@freebsd.org>; Thu, 24 Apr 2008 07:22:52 +0000 (UTC)
	(envelope-from rwatson@FreeBSD.org)
Received: from cyrus.watson.org (cyrus.watson.org [209.31.154.42])
	by mx1.freebsd.org (Postfix) with ESMTP id 436048FC14
	for <hackers@freebsd.org>; Thu, 24 Apr 2008 07:22:52 +0000 (UTC)
	(envelope-from rwatson@FreeBSD.org)
Received: from fledge.watson.org (fledge.watson.org [209.31.154.41])
	by cyrus.watson.org (Postfix) with ESMTP id C0FBD46B0C;
	Thu, 24 Apr 2008 03:22:51 -0400 (EDT)
Date: Thu, 24 Apr 2008 08:22:51 +0100 (BST)
From: Robert Watson <rwatson@FreeBSD.org>
X-X-Sender: robert@fledge.watson.org
To: Bakul Shah <bakul@bitblocks.com>
In-Reply-To: <20080423185431.3FA615BB1@mail.bitblocks.com>
Message-ID: <20080424082155.G10114@fledge.watson.org>
References: <20080423185431.3FA615BB1@mail.bitblocks.com>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed
Cc: Garrett Cooper <yanefbsd@gmail.com>, hackers@freebsd.org
Subject: Re: Fwd: 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: Thu, 24 Apr 2008 07:22:52 -0000


On Wed, 23 Apr 2008, Bakul Shah wrote:

> The *exception* is where a function is explicitly prepared to handle NULLs. 
> One must read its man page carefully and if it doesn't say anything about 
> how NULLs in place of ptrs are handled, one must not pass in NULLs!

While I recognize there are some useful consumer simplicity benefits to 
accepting NULL as an argument to free(3), it's always made me a bit uneasy for 
this reason.

Robert N M Watson
Computer Laboratory
University of Cambridge