Hi,

Can some one please suggest a simple effective and probably platform independent way by which I can create a trial version of an application?

1. The trial version is full featured software, that can be used for either 30 or 60 days.
2. After the trial period, the user should enter the license key in order to use it.
3. When user enters the license key, application should know if the key entered is right or wrong.

I think the way Qt does it is nice (but I have no idea about the internals).

Thanks for suggestions.