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Date: Fri, 19 Mar 2004 12:51:09 -0500
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From: DJ Delorie <dj AT delorie DOT com>
To: djgpp AT delorie DOT com
In-reply-to: <c3f2m1$217i$1@alpha2.radio-msu.net> (akantsel@integra.rmt.ru)
Subject: Re: How can I monitor the amount of free RAM?
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> 1. What memory should I monitor (DOS (below 1MB), upper,...)

Virtual.

> 2. How can do that?

You don't want to monitor free memory, you want to monitor *used*
memory (other things on the computer might use memory too).  Most
programs can use the sbrk(0) call to ask libc where the top of your
memory is.  If it doesn't change, you're not asking for more memory.

The exception is if you choose the "non-moving sbrk" option (nearptr,
DMA, etc need this) in which case your memory range is discontiguous
and sbrk() moves all over the place during allocation.  But at least
you can tell if it changes *at all*.