Message-Id: <m0wf2eX-000S1iC@ciati.edu.ar>
Comments: Authenticated sender is <salvador AT natacha DOT inti DOT edu DOT ar>
From: "Salvador Eduardo Tropea (SET)" <salvador AT inti DOT edu DOT ar>
Organization: INTI
To: James MacDonald <trill AT Xnetbook DOT demon DOT co DOT uk>, djgpp AT delorie DOT com
Date: Fri, 20 Jun 1997 15:38:11 +0000
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Subject: Re: Copy protection and self-modifying EXE's in DJGPP?
Precedence: bulk

James MacDonald <trill AT Xnetbook DOT demon DOT co DOT uk> wrote:

> Copy protection (key-disk)
> --------------------------
> 
> I have a disk formatter that can format lots of weird formats (like
> 1.72Mb, 984Kb on a 720Kb diskette, and any number between). I can create
> my own as well, so if I wanted key disks I'd use floppies formatted to
> 1500Kb for them.
etc....
> Obviously some would be able to get around this protection, BUT the
> normal end user wouldn't by simply copying the disk. TRUE or !TRUE?

Not TRUE, the users knows about good disk-copy utilities to copy strange 
formats (I copied some disks that were supposed to be protected by a laser 
damage and the program was looking for the particular error). That's because 
the one that makes the copies isn't the user itself, is a pirat.
 
> Self-modifying EXE
> ------------------
> 
> Is this possible?
> Some programs can do it. I'd like to be able to patch a registration
> name and serial number into a program. How can this be done with DJGPP?
Why not? You can modify the disk image of your program to put these values.

SET 
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