waiting for user input in separate thread

Question

I am trying to accomplish a way to spawn a thread that waits for user input; if no input is entered within 10 seconds, I want the script to kill off the spawned thread and continue processing. I've got a way to get the input back from the thread if text is entered but I have no way to let the timeout kill off the newly spawned thread.

In the example below is the closest I have come. I tell the newly created thread that it is a daemon and it will exit when the main script exits. The issue that I have with this is that the thread will continue to wait until either the script exits, or the user has inputted something.

shared_var = ['1']
def run(ref):
    ref[0] = raw_input("enter something: ")
    print "shared var changed to '%s'" % (ref[0])

thread = threading.Thread(target=run, args=(shared_var,))
thread.daemon = True  
thread.start()
time.sleep(10)  # simplified timeout

#Need some way to stop thread if no input has been entered
print "shared var = " + shared_var[0]

I know abruptly killing a thread isn't the best way to go (Related Link), but I don't know how to interrupt the new thread waiting on the raw_input

Answer 1

Looks like there is no way to time user input. In the link that SmartElectron provided, the solution does not work since the timer is halted once the raw_input is requested.

Best solution so far is:

# Declare a mutable object so that it can be pass via reference
user_input = [None]

# spawn a new thread to wait for input 
def get_user_input(user_input_ref):
    user_input_ref[0] = raw_input("Give me some Information: ")

mythread = threading.Thread(target=get_user_input, args=(user_input,))
mythread.daemon = True
mythread.start()

for increment in range(1, 10):
    time.sleep(1)
    if user_input[0] is not None:
        break