break/interrupt a time.sleep() in python

Question

I need to break from time.sleep() using ctrl c.

While 1:     time.sleep(60) 

In the above code when the control enters time.sleep function an entire 60 seconds needs to elapsed for python to handled the CTRL C

Is there any elegant way to do it. such that I can interrupt even when the control is in time.sleep function

edit

I was testing it on a legacy implementation which uses python 2.2 on windows 2000 which caused all the trouble . If I had used a higher version of python CTRL C would have interrupted the sleep() . I did a quick hack by calling sleep(1) inside a for loop . which temporarily fixed my issue

Answer 1

The correct answer is to use python stdlib's threading.Event

Sure you can tune down your sleep interval so you sleep for very short periods, but what if you actually want to run your loop once every 60s? Then you need to do more work to determine if it's time to run or just keep sleeping. Furthermore, you're still technically blocking but for only a short period of time. Contrast to threading.Event:

from threading import Event  exit = Event()  def main():     while not exit.is_set():       do_my_thing()       exit.wait(60)      print("All done!")     # perform any cleanup here  def quit(signo, _frame):     print("Interrupted by %d, shutting down" % signo)     exit.set()  if __name__ == '__main__':      import signal     for sig in ('TERM', 'HUP', 'INT'):         signal.signal(getattr(signal, 'SIG'+sig), quit);      main() 

When the signal handler calls exit.set(), the main thread's wait() call will immediately be interrupted.

Now, you could use an Event to signal that there's more work to do, etc. But in this case it does double duty as a convenient indicator that we want to quit (e.g. the while not exit.is_set() part.)

You also have the option to put any cleanup code after your while loop.

Answer 2

Not sure what the sense of this code is - but if necessary use a shorter sleep() interval and put a for loop around it:

for i in range(60):    sleep(1) 

Catching the KeyboardInterrupt exception using try..except is straight-forward