echo-key.py

import sys
import tty
import termios
import signal
from contextlib import contextmanager


@contextmanager
def raw_mode():
    fd = sys.stdin.fileno()
    old_settings = termios.tcgetattr(fd)
    try:
        tty.setraw(fd)
        sys.stdout.write("\033[?1000h")
        sys.stdout.flush()
        yield
    finally:
        termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)


def get_key():
    # not unicode necessarily
    return sys.stdin.buffer.read(1)


def identify_key(char):
    try:
        char = char.decode("utf-8")
    except UnicodeDecodeError:
        pass
    if ord(char) < 32:
        return f"ctrl-{chr(ord(char) + 64)}"
    elif ord(char) == 127:
        return "backspace"
    elif ord(char) <= 127:
        return char
    elif ord(char) >= 127 and ord(char) <= 255:
        return f"alt-{chr(ord(char) - 225 + 97)}"
    else:
        return ord(char)


def main():
    print("Press keys (Ctrl-C to exit):")
    with raw_mode():
        while True:
            char = get_key()
            key_name = identify_key(char)
            print(f"{key_name}", end="")
            sys.stdout.flush()
            if char == b"\x03":
                return


if __name__ == "__main__":
    main()