linux-kernel - Re: Style Question

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <1173622954.3492.13.camel@gimli.at.home>
Date:	Sun, 11 Mar 2007 15:22:34 +0100
From:	Bernd Petrovitsch <bernd@...mix.at>
To:	Cong WANG <xiyou.wangcong@...il.com>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: Style Question

On Sun, 2007-03-11 at 22:15 +0800, Cong WANG wrote:
[...]
> Another question is about NULL. AFAIK, in user space, using NULL is
> better than directly using 0 in C. In kernel, I know it used its own
> NULL, which may be defined as ((void*)0),

Userspace has the usually same definition.

>                                           but it's _still_ different
> from raw zero.

It is different that "0" as such has the type "int". But this int is
automatically promoted to a "0 pointer".

>                So can I say using NULL is better than 0 in kernel?

Yes, because it is immediately clear that a pointer is (or should be)
there (and not an int).
And the same holds for userspace since this is a pure C question.

	Bernd
-- 
Firmix Software GmbH                   http://www.firmix.at/
mobil: +43 664 4416156                 fax: +43 1 7890849-55
          Embedded Linux Development and Services

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/