Date: Mon, 21 Jun 1999 17:12:40 +0300 (IDT)
From: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
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To: Bart Alewijnse <scarfman AT geocities DOT com>
cc: djgpp AT delorie DOT com
Subject: Re: Screen copy
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On Mon, 21 Jun 1999, Bart Alewijnse wrote:

> > If the buffer is contiguous, then use library function `dosmemput'
>
> when wouln't it be? Are you implying unchained mode?

If you need to update only portions of the screen, or if the layout of 
the video memory is such that adjacent pixels don't have adjacent 
addresses, then `dosmemput' is usually less attractive, and it is
recommended to use _farnspokeX functions instead.

> > (it's documented in the library reference).  It already uses the
> > fastest assembly instructions possible.
> Including the move-the-aligned-stuff-and-stick-on-the-odds-and-ends
> thing? I suppose so huh...

Yes, it copies single bytes until either the source or the destination
are aligned on 4-byte boundary, then does the rest with "rep movsl" and 
finally copies the last 3 or less bytes as single bytes.