python multi thread example

multi_thread.py

#!/bin/env python
# -*- coding:utf-8 -*-


import threading


sem = threading.Semaphore(10)
result = []

def run_thread(n):
    with sem:
        global result
        result.append(2*n)
        # print len(threading.enumerate())


def main():
    threads = []

    n = 1000
    for i in xrange(n):
        t = threading.Thread(target=run_thread, args=(i,))
        threads.append(t)

    for i in xrange(n):
        threads[i].start()

    for i in xrange(n):
        threads[i].join()

    print result
    print len(result)


if __name__ == '__main__':
    main()