[rgoulter]

I liked this explanation. https://www.linusakesson.net/programming/tty/

When the TTY device takes (by default) Ctrl+C or Ctrl+D, it sends the signals to the program. The TTY's 'line discipline' (the policy for when the program's STDIN can read from a line of input) can be changed from a default 'cooked' to a 'raw mode'. In with raw mode line discipline the Ctrl+C doesn't send the signal. Presumably that's why e.g. vi or emacs don't just close on Ctrl+C.

[nixpulvis]

> Now you press ^Z. Since the line discipline has been configured to intercept this character (^Z is a single byte, with ASCII code 26), you don't have to wait for the editor to complete its task and start reading from the TTY device. Instead, the line discipline subsystem instantly sends SIGTSTP to the foreground process group.

This helps me, thanks for pointing me back at this great write-up.