Question

I’m looking to terminate some threads after a certain amount of time. These threads will be running an infinite while loop and during this time they can stall for a random, large amount of time. The thread cannot last longer than time set by the duration variable.
How can I make it so after the length set by duration, the threads stop.

def main():
    t1 = threading.Thread(target=thread1, args=1)
    t2 = threading.Thread(target=thread2, args=2)

    time.sleep(duration)
    #the threads must be terminated after this sleep

Answer 1

This will work if you are not blocking.

If you are planing on doing sleeps, its absolutely imperative that you use the event to do the sleep. If you leverage the event to sleep, if someone tells you to stop while “sleeping” it will wake up. If you use time.sleep() your thread will only stop after it wakes up.

import threading
import time

duration = 2

def main():
    t1_stop = threading.Event()
    t1 = threading.Thread(target=thread1, args=(1, t1_stop))

    t2_stop = threading.Event()
    t2 = threading.Thread(target=thread2, args=(2, t2_stop))

    time.sleep(duration)
    # stops thread t2
    t2_stop.set()

def thread1(arg1, stop_event):
    while not stop_event.is_set():
        stop_event.wait(timeout=5)

def thread2(arg1, stop_event):
    while not stop_event.is_set():
        stop_event.wait(timeout=5)