Python: terminating a multi-threaded program after a while using the daemon thread

Question

I want to implement a program that will be completed after starting for some time t, and is tread from the command line using ArgumentParser. I currently have the following code (omit some details):

def run():
    parser = create_arg_parser()
    args = parser.parse_args()
    class_instance = MultiThreadClass(args.arg1, args.arg2)
    class_instance.run()

if __name__ == '__main__':
    run_thread = Thread(target=run)
    run_thread.daemon = True
    run_thread.start()
    time.sleep(3.0)

The program works as I expect (it ends after starting within 3 seconds). But, as I mentioned earlier, the runtime (3.0 in the code snippet above) should be entered from the command line (for example, args.arg3 = 3.0) instead of hard coding. Apparently, I can’t directly deliver time.sleep(args.arg3). I was wondering if there is any approach that could solve my problem? Answers without using a daemon are also welcome! Thank.

PS. If I put the argument analysis code outside the function run, for example:

def run(args):
    class_instance = MultiThreadClass(args.arg1, args.arg2)
    class_instance.run()

if __name__ == '__main__':
    parser = create_arg_parser()
    args = parser.parse_args()
    run_thread = Thread(target=run(args))
    run_thread.daemon = True
    run_thread.start()
    time.sleep(args.arg3)

The program will not end after args.arg3seconds, and I am confused for this reason. I would also be very grateful if anyone could explain the magic behind all of these ... Thank you very much!

Answer 1

Thread , . :

Thread(target=run, args = (args.arg1, args.arg2))

, None run Thread.

, docs daemon = True:

, Python

:

def run(arg1,arg2):
    class_instance = MultiThreadClass(arg1, arg2)
    class_instance.run()

if __name__ == '__main__':
    parser = create_arg_parser()
    args = parser.parse_args()
    run_thread = Thread(target=run, args=(args.arg1, args.arg2))
    run_thread.start()
    time.sleep(args.arg3)

Threads, , docs, "".