How to Hide an applications from taskmanager ?
How to hide an application from task manager?
the application will not be visible in task manager?
Note: it will be visible in process table.
I don't think this is possible (in a convenient way).
Probably you want to run it as a service, it is the only way I know it is possible. Or, depending on the version of Windows (if you are talking about windows) you can try running it from another user, so that it will not be listed in the task manager among the processes of the current user.
As you can imagine, having an application that is able to fake the task manager could be a little dangerous...
Let's just say that Qt does not support this functionality. Any solution you implement will be a platform-dependent solution.