Xref: news2.mv.net comp.os.msdos.djgpp:5009
From: Erik Max Francis <max AT alcyone DOT com>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Speed optimization: memcpy() or for loop ??
Date: Fri, 14 Jun 1996 23:26:05 -0700
Organization: Alcyone Systems
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To: djgpp AT delorie DOT com
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Richard Young wrote:

> A question for the optimization experts:
> 
> For moving data, is it faster to use
> 
> a) memcpy(x,y,n*sizeof(x[0]))
> 
> or
> 
> b) for (i = 0; i < n; i++) x[i] = y[i];
> 
> or are they basically the same speed.

Use the standard library function.

The whole idea behind having such a function is that it is supposed to be a
good implementation of the operation you're interested in.  And, furthermore,
it knows which platform it's running under, so to speak, and so it can do the
right thing.

> With C++ is it better code practice to use b) over a)?

Same thing.

-- 
Erik Max Francis &tSftDotIotE && http://www.alcyone.com/max && max AT alcyone DOT com
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