From:	"Greg Holdridge" <greg AT holdridge7 DOT freeserve DOT co DOT uk>
Newsgroups:	comp.os.msdos.djgpp
Subject:	A mysterious event
Date:	Sun, 13 Aug 2000 17:25:26 +0100
Organization:	Customer of Energis Squared
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To:	djgpp AT delorie DOT com
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Reply-To:	djgpp AT delorie DOT com

I have an assembly function (NASM compiled) called _V_SetMode which takes
one parameter - mode number - for modes 320x200 320x240 320x400 or 360x480.
Anyway, I think something is wrong with it because the following occurs...
using the test code as follows:

// position A
_V_SetMode(4);
// position B
while(!kbhit())
{
   // Plot random pixels
}
V_TextMode();

No problems occur and I get random pixels.  If I insert a call to malloc()
at position B, no problem occurs.  However, a call to malloc() at position A
causes my monitor to switch onto power saving until a key is pressed.  What
sort of problem might there be with the code which would flare up following
this sort of change? malloc() is the only action which appears to cause the
issue.

Any help appreciated,

Greg

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