select

import select
import socket
import queue


server = socket.socket()
server.bind(('localhost',9000))
server.listen(1000)


server.setblocking(False) #不阻塞

msg_dic = {}

inputs = [server,]
#inputs = [server,conn] #[conn,]
#inputs = [server,conn,conn2] #[conn2,]
outputs = [] #
#outputs = [r1,] #
while True:
    readable ,writeable,exceptional= select.select(inputs, outputs, inputs )
    print(readable,writeable,exceptional)
    for r in readable:
        if r is server: #代表来了一个新连接
            conn,addr = server.accept()
            print("来了个新连接",addr)
            inputs.append(conn) #是因为这个新建立的连接还没发数据过来，现在就接收的话程序就报错了，
            #所以要想实现这个客户端发数据来时server端能知道，就需要让select再监测这个conn
            msg_dic[conn] = queue.Queue() #初始化一个队列，后面存要返回给这个客户端的数据
        else: #conn2
            data = r.recv(1024)
            print("收到数据",data)
            msg_dic[r].put(data)

            outputs.append(r) #放入返回的连接队列里
            # r.send(data)
            # print("send done....")

    for w in writeable: #要返回给客户端的连接列表
        data_to_client = msg_dic[w].get()
        w.send(data_to_client) #返回给客户端源数据

        outputs.remove(w) #确保下次循环的时候writeable,不返回这个已经处理完的连接了

    for e in exceptional:
        if e in outputs:
            outputs.remove(e)

        inputs.remove(e)

        del msg_dic[e]


#======================

import socket

HOST = 'localhost'  # The remote host
PORT = 9000  # The same port as used by the server
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((HOST, PORT))
while True:
    msg = bytes(input(">>:"), encoding="utf8")
    s.sendall(msg)
    data = s.recv(1024)

    #
    print('Received', data)
s.close()


http://www.cnblogs.com/alex3714/articles/5248247.html