I am writing a program in python that accepts two inputs.
Once the user gives the first input, he gets 10 seconds to give the second input. If the user is able to provide the second value within those 10 seconds and presses the enter key, the timer stops and goes to the next part of the program.
Is there any functionality in python that allows me to provide an interrupt after the 10 seconds and stop accepting the second input. And if the second input is given, stop the timer.
You can create a custom Timer class and start it in a diffrent thread. Once the timeout occurs (after 10 seconds), you can send a SIGINT signal back to the parent thread, which will raise the KeyboardInterrupt exception that we catch in the main() function. Otherwise you can stop the Timer, after user enters the second input in the right time, which will then stop the Timer thread. Further, we can check if the KeyboardInterrupt happened due to timeout or user action.
Note: While we are sending the signal to the main process, we also need to check, on which platform we are running the programm. See signal.CTRL_C_EVENT and signal.SIGINT.
Demo: https://repl.it/repls/StandardBuoyantProtools
Solution:
import time
import threading
import os
import signal
class Timer(threading.Thread):
_timeout = False
_timer = 0
_stopped = False
def __init__(self, delay):
super(Timer, self).__init__()
self.restart(delay)
def is_timeout(self):
return self._timeout
def stop(self):
self._stopped = True
def restart(self, delay):
self._stopped = False
self._timer = time.time() + delay
def run(self):
while not self._stopped:
time.sleep(0.1)
if time.time() >= self._timer:
break
if not self._stopped:
self._timeout = True
# check os name
if os.name == 'nt':
# we are on Windows
os.kill(os.getpid(), signal.CTRL_C_EVENT)
else:
# we are on a Posix/Unix (or very unlikely on java) system
os.kill(os.getpid(), signal.SIGINT)
def main():
first_input = input('First input:')
delay = 10
timer = Timer(delay)
timer.daemon = True
try:
print('\nStarting the timer for the second input %r second(s)' % delay)
timer.start()
second_input = input('Second input:')
print('\nWell done. Stopping the timer!\n')
timer.stop()
print('Input values: %r %r\n' % (first_input, second_input))
# do your stuff here...
except KeyboardInterrupt:
if timer.is_timeout():
print("\nTimeout!")
else:
print("\nUser interrupted the input")
main()