Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!think.com!zaphod.mps.ohio-state.edu!swrinde!elroy.jpl.nasa.gov!ames!sun-barr!rutgers!mcdhup!inferno!shane
From: shane@inferno.peri.com (Shane Bouslough)
Newsgroups: comp.lang.c
Subject: Re: exploding software
Message-ID: <1991May29.165444.6387@inferno.peri.com>
Date: 29 May 91 16:54:44 GMT
References: <1991May23.221811.21343@agate.berkeley.edu>
Organization: Periphonics Corp.
Lines: 23

cnrdean@cavebear.berkeley.edu writes:
> 
> Anybody know of some standard C code (I need it for Turbo C)
> that will make a program not work after a particular date?
> 

This is a specific example of the general problem of software
copy protection. No method is foolproof. One simple technique
is to write a date at the end of the .exe and have the program
open the file and compare this date to the current date. This
doesn't trash the .exe since the loader knows when to stop reading.

Finding the location of the .exe and other anti-copy protection
problems are left as an exercise.

Interestingly, I wrote a short 10 liner to do this for a friend and
it worked for Zortech and Microsoft but failed for Turbo.

-- 
Shane Bouslough    |  ...!rutgers!mcdhup!inferno!shane           516-467-0500
Periphonics Corp.  |                                             Ride Bike!
4000 Veterans Hwy. |  "We're talking Mega-Ecstasy-Bliss!!!"
Bohemia, NY 11716  |                              -David Lister, Red Dwarf