Hans; Actually, this is not the case on later Mac models, as the OS controls the
fan cooling system. So you can really destroy the Mac by overheating it. I think it may have happened to a MacBook Air here - there were problems with the software in earlier models. Suddenly, it would no more reboot. It happened on a very hot day. Eventually, the motherboard, or something had to be replaced.
Yes, there will be exceptions, on specific models under unusual conditions, I believe there have also been some hard-drives that could be destroyed by software commands in the recent past. However that's A) rare and B) not a issue with the terminal as such. Though it might be possible I wouldn't know how to address the fan speed through Bash here&now.
One can also destroy the Mac by making a poorly written KEXT (kernel extension). It is too slow to let all stuff run as programs, so one can make an extension to the kernel itself, running without the normal kernel checks then. If it sabotages the kernel, then the cooling system may not run properly. I'm not sure this has happened, but it is a theoretical possibility, in fact mentioned on the Darwin-kernel list.
No doubt that's true... but that definitely wouldn't happen by accident and I also feel that that is the kind of design error that a warranty should cover, certainly in the case of computers sold as a matched pair of a OS and hardware. Normal use of the terminal, including the installation of languages like ChucK should -and will- be perfectly safe and normal usage of a computer. Yours, Kas.