How to make an application block the user's work?

Question

Qt

Hello. It is necessary to write a program that cannot be minimized and closed (killed). Or make it so that if the process is killed - it starts again.
Perhaps you can organize using policies, but not in my case. they cannot be used. Well, I want cross-platform).
Regarding non-collapse, there is an idea to catch the minimize event, but you also need to exclude the overlap of the window with others, ctrl-d, alt-tab and others. You can hang your events on the keyboard shortcut, but I'm not sure about the correctness of this decision.
Regarding the indestructibility of the process, there is only one idea so far - to launch a second mini process that controls whether the main process is running. the main process controls the secondary.
What other options do you suggest, I want a beautiful solution.
I think to write in C ++ Qt, but you can choose other frameworks and languages
​​Damn, it looks like a porn blocker, but it's not it. This is something like a daily mandatory questionnaire. Honestly fair.

Answer 1

Under the line, it's easy, you can write a script that (re)launches the program and drives it to the demons.
Well, I'll expand it to the full, QWidget allows you to remove the top panel and frames.