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From: valley@uchicago (Doug Dougherty)
Newsgroups: comp.os.msdos.programmer
Subject: Re: DOS int 21h func 48h
Message-ID: <valley.667832560@gsbsun>
Date: 1 Mar 91 13:02:40 GMT
References: <1991Feb28.193157.27423@digi.lonestar.org>
Sender: news@midway.uchicago.edu (News Administrator)
Distribution: usa
Organization: University of Chicago
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ghuffman@digi.lonestar.org (Gregory Huffman) writes:



(stuff deleted)

>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.

Nitpicks: 1) None of my .COM programs start with ORG 100H.  My assembler
(A86) assumes it unless told otherwise.
2) I've seen lots of .COM programs that start with:

	mov ax,cs	; Set up the segment registers
	mov ds,ax
	mov es,ax
	mov ss,ax

(even though doing so is completely unnecessary, at least under DOS 2.x+)