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Mail Archives: djgpp/1998/06/05/23:33:05

Date: Fri, 5 Jun 1998 23:33:01 -0400 (EDT)
Message-Id: <199806060333.XAA20550@delorie.com>
From: DJ Delorie <dj AT delorie DOT com>
To: jlrubin AT bway DOT net
CC: djgpp AT delorie DOT com
In-reply-to: <3578b2e5.466587@news1.bway.net> (jlrubin@bway.net)
Subject: Re: wanted: demand zero pages for uninitialized static data

> In Dec VAX terminology, a "demand zero page" is an uncommited page
> that is allocated and filled with zeroes the first time it is
> referenced. I hoped that DPMI supported such a thing and all I had to
> do was twiddle some page attribute bits somewhere.
> 
> If it were that simple, I was going to suggest that DJGPP do this by
> default.

It used to be that simple before we switched to DPMI, but DPMI 0.9
doesn't support it.  Unfortunately, DPMI 0.9 is as far as Microsoft
got before they lost interest, so DPMI 1.0 (the one you'd need for
this) is rarely supported, and not by the "big guys".

So, we must pre-initialize BSS at startup.

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