pty_signal_simple.py

import signal
import sys
import time
import pty
from functools import partial

def signal_handler(tag, signum, frame):
    print(f"\n{tag} Received SIGINT, exiting...")
    exit(0)

def get_tag(depth):
    return f"{' ' * (depth * 4)} [{ 'parent' if depth == 0 else 'child' }]"

def main(depth):
    tag = get_tag(depth)
    signal.signal(signal.SIGINT, partial(signal_handler, tag))

    print(f"{tag} Waiting for SIGINT ...")

    if depth < 1:
        print(f"{tag} ================")
        print(f"{tag} Calling pty.spawn() ...")
        pty.spawn([sys.executable, __file__, str(depth + 1), "pty"])

        print(f"{tag} Returned")

    while True:
        time.sleep(1)

if __name__ == "__main__":
    depth = int(sys.argv[1])
    main(depth)