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Mail Archives: djgpp/2000/02/28/21:53:17

Date: Tue, 29 Feb 2000 08:19:16 +0500 (MVT)
From: Prashant TR <prashant_tr AT yahoo DOT com>
X-Sender: prashant_tr AT midpec DOT com
To: Nate Eldredge <neldredge AT hmc DOT edu>
cc: djgpp AT delorie DOT com
Subject: Re: Fastest bitblt?
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On 28 Feb 2000, Nate Eldredge wrote:

> True.  But actually having protection requires also that something set
> what is to be protected.  I.e. you can set the segment limit to
> 0xffffffff.  Limit checking is still active, but I wouldn't consider
> the resulting state to be "protection".

Not entirely true. The MMU protects some portions of the memory, so even
using nearptrs should give you SIGSEGV at times. To map these addresses,
you'll need to use another dangerous call __djgpp_physical_map.

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