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Mail Archives: djgpp-workers/1996/12/17/08:12:39

Date: Tue, 17 Dec 1996 08:08:05 -0500
Message-Id: <199612171308.IAA19872@delorie.com>
From: DJ Delorie <dj AT delorie DOT com>
To: eliz AT is DOT elta DOT co DOT il
CC: djgpp-workers AT delorie DOT com
In-reply-to: <Pine.SUN.3.91.961217135717.21132A-100000@is> (message from Eli
Zaretskii on Tue, 17 Dec 1996 14:00:01 +0200 (IST))
Subject: Re: _dos_ds

> Why does the selector for linear memory have a limit of -1?  Doesn't it 
> mean that anybody who uses the usual dosmemput/farpoke things has a 
> potential to overwrite any address, i.e. the memory protection is 
> disabled?  If so, this is the same as nearptr (except slower), right?
> 
> Is there any problem to make the limit be 1MB?

It used to be 1Mb.  People complained that it should be 16Mb, to cover
the original 286 address space and some I/O boards.  Then people
complained that it needed to cover the Weitek I/O space.  Then people
wanted it to contain the linear frame buffer for SVGA boards.  So now
it's a 4G segment.

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