If you're a button, you have one job: to transmit Morse code from the finger to the machine, Morse code representing a complicated POSIX shell command. And also to power down this entire one-button terminal with a 3 second press, power it up on any button press, with a firmware reset if powered up by a 30 second press.
This is literally the type of thing that caused the THERAC-25 disaster (https://en.wikipedia.org/wiki/Therac-25). Experienced users hitting keys faster than the app could process them, resulting in safety features being inadvertantly bypassed.
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