Writing trial
- Thread starter shannen
- Start date
The easiest way I can think of is to use a file stored on the hard drive. You should make it binary and invisible and possibly encrypted so they can't change the trial end date.
Create that file the first time the program is opened on the computer, and check the current date against the one in the file to see if they still have time left in the trial.
The reason for it being binary is so that they can't open the file in a text editor and change the date.
Create that file the first time the program is opened on the computer, and check the current date against the one in the file to see if they still have time left in the trial.
The reason for it being binary is so that they can't open the file in a text editor and change the date.
Yes, that's true. You could put the file in a very obscure place that isn't even visible in the Finder, such as /usr or /etc. Most Windows apps use the registry for this I think, but I don't believe there's anything like that in OSX.
You can also make the file name really strange like a bunch of letters and numbers, that noone would be able to know what it is.
Another thing you could do, is write the same file to more than one place. If they did delete one, then there'd still be another copy on the disk.
You can also make the file name really strange like a bunch of letters and numbers, that noone would be able to know what it is.
Another thing you could do, is write the same file to more than one place. If they did delete one, then there'd still be another copy on the disk.
No problem. Good luck with your program.
btw, i tried creating a splash screen that has buttons ( try, quit ) for user selection before the launch of my program. I had made the splash screen modal but it cant seem to stop my main program from running until user clicks some stuff ( the splash screen loads, followed by my main program) ? Any idea how I can intercept and hault it? Thanks
binaryDigit
Registered
One note on this. Notice that there is not a single application out there has has not been cracked (at least not one where someone who was interested enough to to bother to try it).
You have to ask yourself why are you trying to limit its use and how much effort you're willing to put into doing it vs how effective it will be. There is no completely fool proof solution. You can do the hidden file thing, until one person finds it and posts it somewhere. You can do the self modifying executable thing which will work until they simply reinstall. Almost ANY attempt can be foiled by someone actually patching your executable to simply jump over your code to check for validity (and of course posting the patch).
If you do go down this road, be darn sure whatever you do absolutely does not interfere with your apps regular use. Nothing will lose you potential customers faster than a PITA copy protection scheme, or one that's flakey.
One approach is to simply state in your EULA that they can use it for X period of time and depend on the honour system. Not very sexy I know, and kinda giving in, but like I said, it just depends on how much time you want to spend on something that eventually will be defeated.
Another approach is to deliver a limited functionality version. Be sure to build a version that truely has those functions missing vs disabled (as someone can figure out how to activate the disabled functions). Not knowing your app it's hard to say what functions you can disable, but you can usually do things like Save or Print.
You have to ask yourself why are you trying to limit its use and how much effort you're willing to put into doing it vs how effective it will be. There is no completely fool proof solution. You can do the hidden file thing, until one person finds it and posts it somewhere. You can do the self modifying executable thing which will work until they simply reinstall. Almost ANY attempt can be foiled by someone actually patching your executable to simply jump over your code to check for validity (and of course posting the patch).
If you do go down this road, be darn sure whatever you do absolutely does not interfere with your apps regular use. Nothing will lose you potential customers faster than a PITA copy protection scheme, or one that's flakey.
One approach is to simply state in your EULA that they can use it for X period of time and depend on the honour system. Not very sexy I know, and kinda giving in, but like I said, it just depends on how much time you want to spend on something that eventually will be defeated.
Another approach is to deliver a limited functionality version. Be sure to build a version that truely has those functions missing vs disabled (as someone can figure out how to activate the disabled functions). Not knowing your app it's hard to say what functions you can disable, but you can usually do things like Save or Print.