linux-kernel - Re: why use memcpy when memmove is there?

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Message-id: <46C06B9F.6080603@shaw.ca>
Date:	Mon, 13 Aug 2007 08:33:03 -0600
From:	Robert Hancock <hancockr@...w.ca>
To:	sk malik <srikrishanmalik@...oo.co.in>
Cc:	linux-kernel@...r.kernel.org
Subject: Re: why use memcpy when memmove is there?

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@...pamshaw.ca
Home Page: http://www.roberthancock.com/

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