Question

I have a python program which needs to clean up something when the shell exits unexpectly, what kind of signal have to be caught?

Answer 1

Use the signal module to add a handler for a specific signal. For example SIGINT and SIGTERM:

import signal
def handler(signum, frame):
    print('Caught signal %d' % signum)
    # Now do something (clean-up?) ...
signal.signal(signal.SIGINT, handler)
signal.signal(signal.SIGTERM, handler)

input() # Example to keep the program running