From:	av568 AT rgfn DOT epcc DOT edu (Beautiful Savior Lutheran Church)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: can someone explain near and farpointer?
Date:	3 May 1997 16:07:28 GMT
Organization:	The Rio Grande Free-Net, El Paso Community College, El Paso, TX
Lines:	22
Message-ID:	<5kfns0$2q3@news.epcc.edu>
References:	<5ke403$iki$1 AT d2 DOT tufts DOT edu>
NNTP-Posting-Host:	rgfn.epcc.edu
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

Brett J. Wiesner (brett AT allegro DOT cs DOT tufts DOT edu) wrote:
> it seems i have to learn what they are and how they effect my machine.
> i've been told that near pointers are quicker (i could use speed, i'm writing
> a 3d lib) but dangerous. while far pointers are slower (slow or slowER?) 

nearptrs are slightly quicker because they use one op, while farptrs use 
two. Both are potentially dangerous if you use them incorrectly, but 
nearptrs are -more- dangerous as the memory protection is turned off, 
potentially for a long time.

> also, what are _dos_ds and _farsetsel and _farnspokeb ???

_dos_ds is the selector for conventional memory that you use in 
conjunction with _far* functions to access conventional memory. 
_farsetsel and _farnspokeb are two of the far pointer functions. For more 
information on all of the far pointer functions, type at your command prompt:

info libc.a alpha _far*

--
Beautiful Savior Evangelical Lutheran Church - av568 AT rgfn DOT epcc DOT edu
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