From:	Nate Eldredge <neldredge AT hmc DOT edu>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: I just got Allegro 3.925 for Windows working...
Date:	Fri, 08 Oct 1999 13:21:11 -0700
Organization:	Harvey Mudd College
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Johnny Chan wrote:
> 
> How can I find out in my program the start location (physical address) and
> the size of itself? I want to show the size of the program and its starting
> address on the screen, how can I do it?

AFAIK, you can't get the physical address of the start of your program. 
The mapping between the virtual memory your program sees and physical
memory is not fixed, so even if you did get an address, it would be
instantly obsolete.

The size, however, is fairly possible (note that it will be the virtual
size).  A reasonable heuristic (I think) is `(((unsigned long)sbrk(0)) -
0x1000)'.  This might be inaccurate in some cases, but I think it should
yield a ballpark figure.

> Also, I wonder what exe file format DJGPP is used? My program need to browse
> thru its PSP to look for some useful informaton, Any suggestion to do that?
> Where to get the file format of DJGPP executable?

The format is called COFF; DJGPP prepends a small .exe stub to allow DOS
to run it.  The spec of the COFF format is (I think) somewhere on
www.delorie.com; the FAQ may have a pointer.
-- 

Nate Eldredge
neldredge AT hmc DOT edu

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