time.sleep blocks while loop in thread

Question

When I run a While True loop in thread and use time.sleep() function the loop stops looping.

I am using this code:

import threading
from time import sleep

class drive_worker(threading.Thread):

    def __init__(self):
        super(drive_worker, self).__init__()
        self.daemon = True
        self.start()

    def run(self):
        while True:
            print('loop')
            #some code
            time.sleep(0.5)

To start the thread I am using this code:

thread = drive_worker()

Answer 1

The loop stops because you flagged the thread as daemon . The program terminates when there are only daemon threads left running.

self.daemon = True # remove this statement and the code should work as expected

Or make the main thread wait for the the daemon thread to finish

dthread = drive_worker()
# no call to start method since your constructor does that
dthread.join() #now the main thread waits for the new thread to finish

Answer 2

You imported sleep as

from time import sleep

so you have to call sleep in run() as sleep(0.5) or you have to change import as

import time which I do not recommend.