How to detect ESCape keypress in Python?

Question

I am running a process in a command window (Windows 7, Python 3.1) where I would like the user to abort the process by pressing Esc key. However, pressing Esc doesn't appear to do anything, the loop never breaks. I have also tried running the script from within my IDE (Wing), but again, the loop cannot be interrupted.

The following is a stripped-down version of my proof-of-concept test...

import msvcrt
import time

aborted = False

for time_remaining in range(10,0,-1):
    # First of all, check if ESCape was pressed
    if msvcrt.kbhit() and msvcrt.getch()==chr(27):
        aborted = True
        break

    print(str(time_remaining))       # so I can see loop is working
    time.sleep(1)                    # delay for 1 second
#endfor timing loop

if aborted:
    print("Program was aborted")
else:
    print("Program was not aborted")

time.sleep(5)  # to see result in command window before it disappears!

If anyone could tell me where I might be going wrong I would be most grateful.

Answer 1

Python 3 strings are unicode and, therefore, must be encoded to bytes for comparison. Try this test:

if msvcrt.kbhit() and msvcrt.getch() == chr(27).encode():
    aborted = True
    break

Or this test:

if msvcrt.kbhit() and msvcrt.getch().decode() == chr(27):
    aborted = True
    break

Or this test:

if msvcrt.kbhit() and ord(msvcrt.getch()) == 27:
    aborted = True
    break

Answer 2

Python 2/3 compatible code:

import time, sys

ESC = '\x1b'
PY3K = sys.version_info >= (3,)
if PY3K:
    from msvcrt import kbhit, getwch as _getch
else:
    from msvcrt import kbhit, getch as _getch
while not kbhit() or _getch() != ESC:
    print(time.asctime())
    time.sleep(1)

Code parts are taken from pager module with more stuff inside.