Message-ID: <33B0CB63.2DBD@bo.dada.it>
Date: Wed, 25 Jun 1997 09:40:19 +0200
From: Diego Zuccato <dz AT bo DOT dada DOT it>
Organization: CyberSpace Software Labs BBS
MIME-Version: 1.0
To: Charles Sandmann <sandmann AT clio DOT rice DOT edu>
CC: Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>,
        djgpp-workers AT delorie DOT com
Subject: Re: Debugging options
References: <9706241842 DOT AA16453 AT clio DOT rice DOT edu>
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Charles Sandmann wrote:

> Nope, been there, done it.  Use sys\mman.h - use PROT_NONE for the boundary
> limit pages (4096 byte boundaries) and use PROT_READ for structures you
> don't want modified.
Does mprotect() get 'any' address ? Or does it need that the passed
address is aligned on a page start ? What happens if it's not aligned ?

> Of course, you need CWSDPMI or 386MAX for this, and a hacked malloc package.  You can use about 1/2 Gb
> of address space with CWSDPMI before the page tables start to fault.
Well, it's documented that it needs some DPMI 1.0 extensions on 0.9
memory blocks. 1/2 GB should be enough, since CWSDPMI can handle 'only'
a maximum of 256MB :-)

> You may find some unix code will work out of the box with this call :-)
Really a good thing :-)

Tks.