#!/usr/bin/env python3


import signal
import subprocess
import sys


def printef(*objects):
    print(*objects, file=sys.stderr, flush=True)


def handler(signum, frame):
    signal.signal(signal.SIGINT, signal.SIG_IGN)
    signal.signal(signal.SIGTERM, signal.SIG_IGN)
    if signum == signal.SIGINT:
        printef('raising KeyboardInterrupt')
        raise KeyboardInterrupt
    else:
        printef('raising SystemExit')
        sys.exit(1)


def subproc():
    printef('subproc:', sys.version_info)
    signal.signal(signal.SIGINT, handler)
    signal.signal(signal.SIGTERM, handler)
    try:
        print('ready', flush=True)
        input()
    except KeyboardInterrupt:
        printef('handling KeyboardInterrupt')
    except SystemExit:
        printef('handling SystemExit')
    except:
        printef('handling something else:', sys.exc_info())
    finally:
        printef('doing finally')


def main():
    proc = subprocess.Popen(
        [sys.executable, __file__, 'subproc'],
        stdin=subprocess.PIPE,
        stdout=subprocess.PIPE)
    # readline() to ensure that the signal handlers are already set
    ready = proc.stdout.readline().decode().strip()
    assert ready == 'ready'
    proc.send_signal(signal.SIGINT)
    proc.send_signal(signal.SIGTERM)
    rc = proc.wait()
    print('rc:', rc)
    sys.exit(rc)


if __name__ == '__main__':
    if 'subproc' in sys.argv:
        subproc()
    else:
        main()