Asynchronous execution with blocking while loop

Question

So this is my scenario. I have a python script that runs in an infinite while loop which takes in user input.

But I now want another function to to do stuff every n seconds while the main loop, which is blocking (waiting for python's input() function), is still running. I have looked into asyncio and scheduling but they don't seem to work with blocking function calls, or am I mistaking?

I have looked into multiprocessing but couldn't wrap my head around how exactly I would be supposed to do that yet.

EDIT:

if __name__ == "__main__":
    def survivor():
        count = 5
        while count:
            print("alive")
            time.sleep(8)
            count -= 1
        print("done")


    test = JobChainClient()

    cli = threading.Thread(name="cli", target=test.getShell())
    network = threading.Thread(name="network", target=survivor())

    cli.start()
    network.start()
    print("Done")

This code gets my CLI which is a infinite while loop and my network daemon. When I run this it obviously works but the problem is this:

(JobChain) > exit
Closing JobChain client now!
alive
alive
alive

My loop breaks after the exit command and only than does the other thread start, I probably just missed something here, please correct me.

user4815162342 user4815162342 · Accepted Answer · 2018-02-19T11:46:20

The simplest solution is to call this other function (that does stuff every n seconds) in a separate thread.

If you want to use asyncio, look into aioconsole which provides the async equivalent of input().

EDIT
Regarding the updated question, the correct way to start a thread is:

# note the lack of parentheses after `getShell` - you only
# want to refer to the function, not to call it (yet)
cli = threading.Thread(name="cli", target=test.getShell)
cli.start()

Asynchronous execution with blocking while loop

2 Answers