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While neat, this is not self-sustaining — it’s taking more energy to power it than you’re getting out of it. (You can build a fusion device on your garage if you’re so inclined, though obviously this is much neater than that!)
One viewpoint is that we’ll never get clean energy from these devices, not because they won’t work, but because you get a lot of neutrons out of these devices. And what do we do with neutrons? We either bash them into lead and heat stuff up (boring and not a lot of energy), or we use them to breed fissile material, which is a lot more energetically favorable. So basically, the economically sound thing to do is to use your fusion reactor to power your relatively conventional fission reactor. Which is still way better than fossil fuels IMHO, so that’s something.
IIRC
chvt
is a privileged command, which makes sense (if an unprivileged user could execute this command they could effectively brick the computer for a local user).That said, my understanding is that modern DE’s are given a lot of access, so presumably
chvt
is allowed (and in this case, is required because as others mentioned, password is required). So the only other option is to fail unlocked, which is all kinds of Bad.