Disable physical buttons

I bet this guy he couldn't disable the ability to turn off my computer via the button on the front of the case.
He sent me this program, and it worked. I tried to turn it off by the main 'on/off' button but it wouldn't work and i had to turn it off by the switch on the PSU.
How is this possible?

that's a pretty impressive program, actually kind of disturbing, because as far as i know the soft reset is one of the lowest level interrupts there is. i could be wrong and your OS provides a way to disable it, though.