Python多线程变量溢出问题，python多线程溢出,代码如下python#!

Python多线程变量溢出问题，python多线程溢出,代码如下python#!

代码如下

python#!/usr/bin/env python# -*- coding: utf-8 -*-import socket,time,threadingtask_num=0lock = threading.Lock()def loop4thread():    global task_num    while task_num < 100:        lock.acquire()        try:            print "%s Doing NO.%d Task..." %(threading.current_thread().name , task_num)            task_num+=1        finally:            lock.release()onethread=[ 0 for x in range(10)]for i in range(10) :    onethread[i] = threading.Thread(target=loop4thread,name="Threadloop"+str(i))    onethread[i].start()

输出结果 最后一行是
Doing No.108 Task...

可是我在loop4thread函数中写了 在 task_num <100 才执行啊，

为什么 task_num 溢出到 108 呢

def loop4thread():    global task_num    while True:        lock.acquire()        if task_num >= 100:            lock.release()            break        try:            print "%s Doing NO.%d Task..." %(threading.current_thread().name , task_num)            task_num+=1        finally:            lock.release()

编橙之家文章，