线程间通信queue

以生产者和消费者为例，说明线程间通信
Queue是线程间安全类， queue.Queue 类内部使用一个列表（或其他容器）来存储项目，并使用一个互斥锁（mutex）来保护数据结构的完整性。

#! /usr/bin/python
#coding=utf-8
# filename: downloadfile.py

import os,urllib.request,re
from multiprocessing import Queue
import threading

q = Queue()
bover = False
def opensrc():
    fo = open('source.csv')           
    line = fo.readline()
    while line: 
       line = fo.readline()
       line = line[:-1]
       q.put(line)

    fo.close()
    bover = True

def worker():
    while(True):
       line = q.get(block=False)
       if line == '' and bover == True:
          break
       if line == '':
          continue

       strs = line.split(',')

       conno = strs[1]
       conno = conno[1:-1]
          
       filename = strs[3]
       filename = filename[1:-1]
       filename = conno+'_'+filename
       print(filename)

       url = strs[4]
       url = url[1:-1]
       print(url)
       data = urllib.request.urlopen(url).read()
       with open(filename, 'wb') as fw:
          fw.write(data)
          print('download',filename,' ok.')
          fw.close()

if __name__ == '__main__':
    rt = threading.Thread(target=opensrc)
    rt.start()
    rt.join()
    wts = []
    for i in range(100):
      wts.append(threading.Thread(target=worker))
       wts[i].start()
    
    for i in range(100):
       wts[i].join()

print("download all.")