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From: Robert Hancock <hancockr@shaw.ca>
To: sk malik <srikrishanmalik@yahoo.co.in>
Cc: linux-kernel@vger.kernel.org
Subject: Re: why use memcpy when memmove is there?
Date: Mon, 13 Aug 2007 08:33:03 -0600	[thread overview]
Message-ID: <46C06B9F.6080603@shaw.ca> (raw)
In-Reply-To: <fa.tH0XPZg4jvmqSQh3iOmzbwrRN9Y@ifi.uio.no>

sk malik wrote:
> Hi, All
> 
> We were looking at  "[kernel]/lib/string.c"
> (http://lxr.linux.no/source/lib/string.c#L500)
> 
> memcpy copies a part of memory to some other location
> but It will not work for all cases of overlapping
> blocks.(if the start of destination block falls
> between the source block)
> 
> while memove copes with overlapping areas.
> 
> then why is memcpy present in the sources can't we
> simply do
> 
> "#define memcpy memmove" in include/linux/string.h
> 
> or am I missing something?

Because the assumption that the areas don't overlap means memcpy can be 
more efficient.

-- 
Robert Hancock      Saskatoon, SK, Canada
To email, remove "nospam" from hancockr@nospamshaw.ca
Home Page: http://www.roberthancock.com/


       reply	other threads:[~2007-08-13 16:05 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <fa.tH0XPZg4jvmqSQh3iOmzbwrRN9Y@ifi.uio.no>
2007-08-13 14:33 ` Robert Hancock [this message]
2007-08-13 10:55 why use memcpy when memmove is there? sk malik
2007-08-13 14:15 ` Jan Engelhardt
2007-08-13 15:02 ` Stefan Richter
2007-08-14 21:59 ` David Schwartz

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