linux-kernel - Re: [PATCH 4/4] fs/qnx4: decrement sizeof size in strncmp

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Message-ID: <1258070775.9696.20.camel@Joe-Laptop.home>
Date:	Thu, 12 Nov 2009 16:06:15 -0800
From:	Joe Perches <joe@...ches.com>
To:	David Wagner <daw-news@...berkeley.edu>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: [PATCH 4/4] fs/qnx4: decrement sizeof size in strncmp

On Thu, 2009-11-12 at 23:49 +0000, David Wagner wrote:
> Julia Lawall  wrote:
> > As observed by Joe Perches, sizeof of a constant string includes the
> > trailing 0.  If what is wanted is to check the initial characters of
> > another string, this trailing 0 should not be taken into account.  If an
> > exact match is wanted, strcmp should be used instead.
> A caution: Your patch changes behavior.  Is there a specific reason
> to believe that the change in behavior is what is desired/intended in
> this context?  Lacking any analysis that indicates that the change in
> behavior is desired, I'm skeptical that a behavior-changing patch should
> be applied.

I agree that desired behavior should be known before
patches are applied.

Most likely, this instance should just be strcmp.

That gives better readability, trivially improved
performance, and easier verification.

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