Anyone have any links to information on coding "time-limited" trial applications? I've got several programs that I would like to make demo's of that function for like 15 days or so, but I'm not really sure how to do this in a way that couldn't easily be cracked...
http://www.programmersheaven.com/default.htm
Enter "time limit" in the search box
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Thanks, but I'm not really looking to just reuse some else's code or library, I'm really more interested in creating my own and learning about some of the methods that you can use to achieve this, and what their pro's and con's are...
DanMan,
It can all be easily cracked. Back when I was a kid, and into all that, time limits where the easiest things to disable. I don't know how it is now, but back then, the toughest protections always used some form of encryption.
I can't say for sure.....but that doesn't look work related.
Well, time-limited software these days is (usually) much more difficult to crack for the reason you just said: encryption (usually of the actual executable file, which is wrapped in a special program who's sole purpose is to make cracking more difficult). If I just created a simple file the first time the program was run that contained the date the program was first run and checked that file each time the program was run, it would be VERY simple to crack: all the person would have to do is delete the file, and the program would just recreate it.
Another option would be to hide a key somewhere in the registry that the program could check. This could be cracked, but would be much more difficult. However, this program needs to run on Unix systems as well as Win32/NT, so I can't use Win32 functions unless there is a close equivalent for Unix (I don't think Unix has a registry or anything similar, but I could be wrong since I know very little about it).
So, anyone have any ideas? I'm running low here...
