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From: ghuffman@digi.lonestar.org (Gregory Huffman)
Newsgroups: comp.os.msdos.programmer
Subject: DOS int 21h func 48h
Message-ID: <1991Feb28.193157.27423@digi.lonestar.org>
Date: 28 Feb 91 19:31:57 GMT
Sender: ghuffman@digi.lonestar.org (Gregory Huffman)
Distribution: usa
Organization: DSC Communications, Plano Tx.
Lines: 37



Hello DOS Programmers:

Here is the promised summary of my int 21h func 48h dynamic memory
allocation problem.

First of all, I want to thank everyone that replied to my question.  I
tried to personally respond to each person, but I have been having some
difficulty sending out going mail.  Most of it bounced back.

In my code I was trying to dynamically allocate memory using a DOS service
call.  

One person sugested that my *.exe program was claiming all the available
memory and that I should issue a call to resize the available memory.  This
is a very good suggestion that I will explore.

Another person actually compiled and linked the code on their system and it
performed as I wanted it to (dynamic memory was allocated as a result of 
the DOS service call).  This may indicate that I have a problem in another
area of my system that needs exploring.

Many people thought I was creating a *.com file.  I was not.  

Three things are being done that indicates this is a *.exe program.
The first sign is I'm creating stack space in this module.  The second sign
is their is no ORG 100H statement.  All *.com programs must have 
cs:100h as the entry point.  And finally, I'm loading segment registers ds
and es at runtime.  This can not be done in *.com programs.

Your comments have been appreciated.  I thank all that spent time on this.


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Greg Huffman	Internet	ghuffman@.digi.lonestar.org    *
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