The I/O thread stops terminal input from showing after program stops running

[mLaHire]

VM I/O threads seem to capture Stdout and Stdin even after the program ends.

Possible solution: use bit 14 of KBSR and DSR as a kill signal; 0 => okay, 1 => exit I/O threads.

EDIT: note, only discovered on Ubuntu 18 LTS & Kubuntu 24 LTS, not present on Windows 10

[mLaHire]

Partial resolution, new problem is that program waits for key input on exit. Future solution? Nested threads, tx_rx for input handler

[mLaHire]

Current stopgap -- "press any key to exit..." on exit.