Date:	Mon, 21 Jun 1999 09:11:16 +0300 (IDT)
From:	Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
X-Sender:	eliz AT is
To:	Bart Alewijnse <scarfman AT geocities DOT com>
cc:	djgpp AT delorie DOT com
Subject:	Re: Screen copy
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On 20 Jun 1999, Bart Alewijnse wrote:

> How do you copy a double buffer to the screen the fastest?

If the buffer is contiguous, then use library function `dosmemput'
(it's documented in the library reference).  It already uses the
fastest assembly instructions possible.

> Are there any other ways to do this? What's a fast one/the fastest?
> I suppose that for the LFB it'd just be memcpy

`dosmemput' uses essentially the same code as `memcpy', except that it
``wastes'' a single instruction to load _dos_ds into a segment
register before commencing the transfer.

If you are really interested in knowing the innards of library
functions, I suggest to download djlsr202.zip and study their
sources.

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