python thread

注意queue, setDaemon。

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

from threading import Thread

import subprocess

from Queue import Queue



num_threads = 3

ips = ['10.108.100.174', '119.75.218.77', '127.0.0.1']

q = Queue()



def pingit(i, queue):

    while True:

        ip = queue.get()

        print "thread %s is pinging %s" % (i, ip)

        ret = subprocess.call('ping -c 3 %s' % ip, shell=True, stdout=open('/dev/null','w'))#正常则返回0，异常则返回1；stdout=open('/dev/null','w')屏蔽ping具体细节信息

        if ret != 0:

            print "%s is down" % ip

        queue.task_done()



for i in xrange(num_threads):#xrang比range好

    t = Thread(target=pingit, args=(i, q))

    t.setDaemon(True)#设置了setDaemon则线程会随着主线程关闭而关闭，python中，主线程结束后，会默认等待子线程结束后，主线程才退出

    t.start()



for ip in ips:

    q.put(ip)



print "main thread is waiting..."

q.join()

print "Done..."