How do I capture SIGINT in Python?

Question

I'm working on a python script that starts several processes and database connections. Every now and then I want to kill the script with a Ctrl+C signal, and I'd like to do some cleanup.

In Perl I'd do this:

$SIG{'INT'} = 'exit_gracefully';  sub exit_gracefully {     print "Caught ^C \n";     exit (0); } 

How do I do the analogue of this in Python?

Answer 1

Register your handler with signal.signal like this:

#!/usr/bin/env python import signal import sys  def signal_handler(sig, frame):     print('You pressed Ctrl+C!')     sys.exit(0)  signal.signal(signal.SIGINT, signal_handler) print('Press Ctrl+C') signal.pause() 

Code adapted from here.

More documentation on signal can be found here.  

Answer 2

You can treat it like an exception (KeyboardInterrupt), like any other. Make a new file and run it from your shell with the following contents to see what I mean:

import time, sys  x = 1 while True:     try:         print x         time.sleep(.3)         x += 1     except KeyboardInterrupt:         print "Bye"         sys.exit()