Message-Id: <200007032021.XAA00806@mailgw1.netvision.net.il>
Date: Mon, 03 Jul 2000 23:22:12 +0200
To: Nate Eldredge <neldredge AT hmc DOT edu>
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From: "Eli Zaretskii" <eliz AT is DOT elta DOT co DOT il>
CC: djgpp AT delorie DOT com
In-reply-to: <83u2e7ugxf.fsf@mercury.bitbucket> (message from Nate Eldredge on
	03 Jul 2000 12:55:56 -0700)
Subject: Re: Where can I get a Thread safe malloc debugger?
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> From: Nate Eldredge <neldredge AT hmc DOT edu>
> Newsgroups: comp.os.msdos.djgpp
> Date: 03 Jul 2000 12:55:56 -0700
> > 
> > No, it won't, not unless you have a DPMI 1.0 server which supports 
> > page-level protection.  Sorry.
> 
> This is exactly what YAMD does, actually.

I don't think so.  IIRC, YAMD unmaps pages from the program's address
space using a call that CWSDPMI supports (the same call that is
requirted for NULL pointer protection).  Electric Fence needs more
than that: it needs protection at page level (as opposed to at segment
level).  I forget the details, but anyone who looks at the sources
will see it.