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From: Dan Carpenter <dan.carpenter@oracle.com>
To: Joe Perches <joe@perches.com>
Cc: devel@driverdev.osuosl.org, gregkh@linuxfoundation.org,
	Amitoj Kaur Chawla <amitoj1606@gmail.com>,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH] Staging: rtl8188eu: Remove zero testing pointer typed value
Date: Sat, 4 Apr 2015 00:04:59 +0300	[thread overview]
Message-ID: <20150403210458.GV10964@mwanda> (raw)
In-Reply-To: <1428080470.13180.19.camel@perches.com>

On Fri, Apr 03, 2015 at 10:01:10AM -0700, Joe Perches wrote:
> On Fri, 2015-04-03 at 19:51 +0300, Dan Carpenter wrote:
> > Also strcmp() and similar should always be done as == 0, < 0 or != 0
> > because that is the idiom:
> 
> Less true.
> 
> When testing for equality, !strcmp is very common.
> 
> There are ~2500 uses of !strcmp in the kernel tree vs
> ~1500 uses of strcmp() == or !=

Bugs with reversed strcmp() tests are almost always caught in testing so
it's not an issue.  But == 0 is more correct.  ;)

1)  It's more clear when read in English.  "if not strcmp then" or
"if strcmp NOT EQUAL zero".  In the second one I've emphasized the
NOT EQUAL because the strings are not eqaul.

2)  Also if works for the other compares too.

	if (strcmp(x, y) < 0)  <-- means x is less than y.
	if (strcmp(x, y) == 0) <-- means x == y.

regards,
dan carpenter

  reply	other threads:[~2015-04-03 21:05 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-04-03 16:42 [PATCH] Staging: rtl8188eu: Remove zero testing pointer typed value Amitoj Kaur Chawla
2015-04-03 16:51 ` Dan Carpenter
2015-04-03 17:01   ` Joe Perches
2015-04-03 21:04     ` Dan Carpenter [this message]
2015-04-04 13:58       ` Dan Carpenter
2015-04-04 15:52         ` Joe Perches
2015-04-03 17:03   ` Amitoj Kaur Chawla

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