Question

I’m trying to wrap the blocking calls in pyaudio with a thread to give me non-blocking access through queues. However, the problem I have is not with pyaudio, or queues, but with the issue of trying to test a thread. In keeping with “strip the example down to the minimum possible”, all the pyaudio stuff has vanished, to leave only the thread class, and its instantiation in a main.

What I was hoping for was an object that I could create, and leave to get on with its stuff in the background, while I do control things with the console or tk. I figure the following max-stripped down example should have the thread doing stuff, while main runs and asks me if it is working. The raw_input prompt never appears. I would not be surprised at this if I was running it from IDLE, which is not thread safe, but I get the same behaviour if I run the script directly from the OS. I was prepared to see the raw input prompt disappear up the screen pushed by ‘running’ prints, but not even that happens. The prompt never appears. What’s going on? It does respond to ctrl-C and to closing the window, but I’d still like to be able to see main running.

import threading
import time

class TestThread(threading.Thread):
    def __init__(self):
        threading.Thread.__init__(self)
        self.running=True
        self.run()

    def run(self):        
        while self.running:
            time.sleep(0.5)
            print 'running'                            

    def stop(self):
        self.running=False

if __name__=='__main__':

    tt=TestThread()
    a=raw_input('simple stuff working ? -- ')
    tt.stop()

Answer 1

You should start the thread with self.start() instead of self.run(). In this case you are just running the thread function like any other normal function.