Question

Is there a way to send an interrupt to a python module when the user inputs something in the console? For example, if I’m running an infinite while loop, i can surround it with a try/except for KeyboardInterrupt and then do what I need to do in the except block.

Is there a way to duplicate this functionality with any arbitrary input? Either a control sequence or a standard character?

Edit: Sorry, this is on linux

Answer 1

Dependent on the operating system and the libraries available, there are different ways of achieving that. This answer provides a few of them.

Here is the Linux/OS X part copied from there, with in infinite loop terminated using the escape character. For the Windows solution you can check the answer itself.

import sys
import select
import tty
import termios

from curses import ascii

def isData():
    return select.select([sys.stdin], [], [], 0) == ([sys.stdin], [], [])

old_settings = termios.tcgetattr(sys.stdin)
try:
    tty.setcbreak(sys.stdin.fileno())

    i = 0
    while 1:
        print i
        i += 1

        if isData():
            c = sys.stdin.read(1)
            if c == chr(ascii.ESC):
                break

finally:
    termios.tcsetattr(sys.stdin, termios.TCSADRAIN, old_settings)

Edit: Changed the character detection to use characters as defined by curses.ascii, thanks to Daenyth’s unhappiness with magic values which I share.