Python 3 Timed Input
If it is acceptable to block the main thread when user haven't provided an answer:
from threading import Timer
timeout = 10
t = Timer(timeout, print, ['Sorry, times up'])
t.start()
prompt = "You have %d seconds to choose the correct answer...\n" % timeout
answer = input(prompt)
t.cancel()
Otherwise, you could use @Alex Martelli's answer (modified for Python 3) on Windows (not tested):
import msvcrt
import time
class TimeoutExpired(Exception):
pass
def input_with_timeout(prompt, timeout, timer=time.monotonic):
sys.stdout.write(prompt)
sys.stdout.flush()
endtime = timer() + timeout
result = []
while timer() < endtime:
if msvcrt.kbhit():
result.append(msvcrt.getwche()) #XXX can it block on multibyte characters?
if result[-1] == '\r':
return ''.join(result[:-1])
time.sleep(0.04) # just to yield to other processes/threads
raise TimeoutExpired
Usage:
try:
answer = input_with_timeout(prompt, 10)
except TimeoutExpired:
print('Sorry, times up')
else:
print('Got %r' % answer)
On Unix you could try:
import select
import sys
def input_with_timeout(prompt, timeout):
sys.stdout.write(prompt)
sys.stdout.flush()
ready, _, _ = select.select([sys.stdin], [],[], timeout)
if ready:
return sys.stdin.readline().rstrip('\n') # expect stdin to be line-buffered
raise TimeoutExpired
Or:
import signal
def alarm_handler(signum, frame):
raise TimeoutExpired
def input_with_timeout(prompt, timeout):
# set signal handler
signal.signal(signal.SIGALRM, alarm_handler)
signal.alarm(timeout) # produce SIGALRM in `timeout` seconds
try:
return input(prompt)
finally:
signal.alarm(0) # cancel alarm
Interesting problem, this seems to work:
import time
from threading import Thread
answer = None
def check():
time.sleep(2)
if answer != None:
return
print("Too Slow")
Thread(target = check).start()
answer = input("Input something: ")