Question

Let’s say I have a loop that’ll take a while to finish, like reading a long file. How do I make it so every period of time, x (milliseconds?), I execute “some code”?

while inFile.readable():
    line = inFile.readline()
    print(line)   # I want to do this every few seconds

I’d like to do this via threading and lambdas, as an exercise.

Answer 1

For example:

import thread, time

def takes_a_while():

    def print_status():
        while True:
            print i   # print current i every two seconds
            time.sleep(2)

    status_thread = thread.start_new_thread(print_status, ())
    for i in xrange(10000000):
        print '*',
        time.sleep(0.1)
    status_thread.exit()

takes_a_while()

Can be done nicer with decorators or contexts, but you got the idea.