import os
import random
import sys
import time
import threading

thread_has_run = set()

def random_io():
    '''Loop for a while sleeping random tiny amounts and doing some I/O.'''
    while True:
        in_f = open(os.__file__, 'rb')
        stuff = in_f.read(200)
        null_f = open(os.devnull, 'wb')
        null_f.write(stuff)
        time.sleep(random.random() / 1995)
        null_f.close()
        in_f.close()
        thread_has_run.add(threading.current_thread())

def main():
    count = 0
    for _ in range(40):
        new_thread = threading.Thread(target=random_io)
        new_thread.daemon = True
        new_thread.start()
        count += 1
    while len(thread_has_run) < count:
        time.sleep(0.001)
    # Trigger process shutdown
    sys.exit(0)

main()