An inescapable while loop in Python

fman is programmed in Python. While hunting a bug today, I realised I've been making a mistake for the past 6 years. Consider the following code:

from time import sleep
while True:

What do you think happens when you press Ctrl+C? I would have expected to get out of the infinite loop. But it doesn't work! You have to press Ctrl+Z to suspend the process.

The reason for this is that the empty except: catches everything, including the KeyboardInterrupt that is raised when you press Ctrl+C. Instead, what you'll most likely want is:

except Exception:

This catches the exceptions you're normally interested in but leaves others like KeyboardInterrupt or SystemExit unharmed. No more except: for me!

fman is a file manager with a Python API. If you liked this post, you should check it out!

Michael started fman in 2016, convinced that we deserve a better file manager. fman's launch in 2017 was a huge success. But despite full-time work, it only makes $350 per month. The goal for 2018 is to fix this.