#coding:UTF8

 import select

 import socket

 import sys

 import Queue

 #创建一个TCP/IP 进程

 server = socket.socket(socket.AF_INET,socket.SOCK_STREAM)

 server.setblocking(0)

 #连接地址和端口

 server_address = ('localhost',10000)

 print >>sys.stderr,'starting up on %s prot %s' % server_address

 server.bind(server_address)

 #最大允许链接数

 server.listen(5)

 inputs = [ server ]

 outputs = []

 message_queues = {}

 while inputs:

     print >>sys.stderr,'\nwaiting for the next event'

     readable,writable,exceptional = select.select(inputs,outputs,inputs)

     # Handle inputs

     for s in readable:

         if s is server:

             # A "readable" server socket is ready to accept a connection

             connection, client_address = s.accept()

             print >>sys.stderr, 'new connection from', client_address

             #connection.setblocking(0)

             inputs.append(connection)

             # Give the connection a queue for data we want to send

             message_queues[connection] = Queue.Queue()

         else:

             data = s.recv(1024)

             if data:

                 # A readable client socket has data

                 print >>sys.stderr, 'received "%s" from %s' % (data, s.getpeername())

                 message_queues[s].put(data)  #这个s相当于connection

                 # Add output channel for response

                 if s not in outputs:

                     outputs.append(s)

             else:

                 # Interpret empty result as closed connection

                 print >>sys.stderr, 'closing', client_address, 'after reading no data'

                 # Stop listening for input on the connection

                 if s in outputs:

                     outputs.remove(s)  #既然客户端都断开了，我就不用再给它返回数据了，所以这时候如果这个客户端的连接对象还在outputs列表中，就把它删掉

                 inputs.remove(s)    #inputs中也删除掉

                 s.close()           #把这个连接关闭掉

                 # Remove message queue

                 del message_queues[s]

     # Handle outputs

     for s in writable:

         try:

             next_msg = message_queues[s].get_nowait()

         except Queue.Empty:

             # No messages waiting so stop checking for writability.

             print >>sys.stderr, 'output queue for', s.getpeername(), 'is empty'

             outputs.remove(s)

         else:

             print >>sys.stderr, 'sending "%s" to %s' % (next_msg, s.getpeername())

             s.send(next_msg.upper())

     # Handle "exceptional conditions"

     for s in exceptional:

         print >>sys.stderr, 'handling exceptional condition for', s.getpeername()

         # Stop listening for input on the connection

         inputs.remove(s)

         if s in outputs:

             outputs.remove(s)

         s.close()

         # Remove message queue

         del message_queues[s]     

server

# Sockets from which we expect to read

inputs = [ server ]

# Sockets to which we expect to write

outputs = [ ]

# Outgoing message queues (socket:Queue)

message_queues = {}

while inputs:

    # Wait for at least one of the sockets to be ready for processing

    print >>sys.stderr, '\nwaiting for the next event'

    readable, writable, exceptional = select.select(inputs, outputs, inputs)

当你把inputs,outputs,exceptional(这里跟inputs共用)传给select()后，它返回3个新的list，我们上面将他们分别赋值为readable,writable,exceptional, 所有在readable list中的socket连接代表有数据可接收(recv),所有在writable list中的存放着你可以对其进行发送(send)操作的socket连接，当连接通信出现error时会把error写到exceptional列表中。

 #coding:UTF8

 import socket

 import sys

 messages = [ 'This is the message. ',

              'It will be sent ',

              'in parts.',

              ]

 server_address = ('localhost', 10003)

 # Create a TCP/IP socket

 socks = [ socket.socket(socket.AF_INET, socket.SOCK_STREAM),

           socket.socket(socket.AF_INET, socket.SOCK_STREAM),

           ]

 # Connect the socket to the port where the server is listening

 print >>sys.stderr, 'connecting to %s port %s' % server_address

 for s in socks:

     s.connect(server_address)

 for message in messages:

     # Send messages on both sockets

     for s in socks:

         print >>sys.stderr, '%s: sending "%s"' % (s.getsockname(), message)

         s.send(message)

     # Read responses on both sockets

     for s in socks:

         data = s.recv(1024)

         print >>sys.stderr, '%s: received "%s"' % (s.getsockname(), data)

         if not data:

             print >>sys.stderr, 'closing socket', s.getsockname()

server：

starting up on localhost prot 10000

waiting for the next event

new connection from ('127.0.0.1', 54812)

waiting for the next event

new connection from ('127.0.0.1', 54813)

received "This is the message. " from ('127.0.0.1', 54812)

waiting for the next event

received "This is the message. " from ('127.0.0.1', 54813)

sending "This is the message. " to ('127.0.0.1', 54812)

waiting for the next event

output queue for ('127.0.0.1', 54812) is empty

sending "This is the message. " to ('127.0.0.1', 54813)

waiting for the next event

output queue for ('127.0.0.1', 54813) is empty

waiting for the next event

received "It will be sent " from ('127.0.0.1', 54812)

received "It will be sent " from ('127.0.0.1', 54813)

waiting for the next event

sending "It will be sent " to ('127.0.0.1', 54812)

sending "It will be sent " to ('127.0.0.1', 54813)

waiting for the next event

output queue for ('127.0.0.1', 54812) is empty

output queue for ('127.0.0.1', 54813) is empty

waiting for the next event

received "in parts." from ('127.0.0.1', 54812)

received "in parts." from ('127.0.0.1', 54813)

waiting for the next event

sending "in parts." to ('127.0.0.1', 54812)

sending "in parts." to ('127.0.0.1', 54813)

waiting for the next event

output queue for ('127.0.0.1', 54812) is empty

output queue for ('127.0.0.1', 54813) is empty

waiting for the next event

closing ('127.0.0.1', 54813) after reading no data

closing ('127.0.0.1', 54813) after reading no data

waiting for the next event

client：

connecting to localhost port 10000

('127.0.0.1', 54812): sending "This is the message. "

('127.0.0.1', 54813): sending "This is the message. "

('127.0.0.1', 54812): received "THIS IS THE MESSAGE. "

('127.0.0.1', 54813): received "THIS IS THE MESSAGE. "

('127.0.0.1', 54812): sending "It will be sent "

('127.0.0.1', 54813): sending "It will be sent "

('127.0.0.1', 54812): received "IT WILL BE SENT "

('127.0.0.1', 54813): received "IT WILL BE SENT "

('127.0.0.1', 54812): sending "in parts."

('127.0.0.1', 54813): sending "in parts."

('127.0.0.1', 54812): received "IN PARTS."

('127.0.0.1', 54813): received "IN PARTS."

#coding: utf-8 

import select, socket

response = b"hello world"

serversocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

serversocket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

serversocket.bind(('localhost', 10000))

serversocket.listen(1)

serversocket.setblocking(0)

#

poll = select.poll()

poll.register(serversocket.fileno(), select.POLLIN)

connections = {}

while True:

    for fd, event in poll.poll():

        if event == select.POLLIN:

            if fd == serversocket.fileno():

                con, addr = serversocket.accept()

                poll.register(con.fileno(), select.POLLIN)

                connections[con.fileno()] = con

            else:

                con = connections[fd]

                data = con.recv(1024)

                if data:

                    poll.modify(con.fileno(), select.POLLOUT)

        elif event == select.POLLOUT:

            con = connections[fd]

            con.send(response)

            poll.unregister(con.fileno())

            con.close()

 #coding:Utf8

 import socket, select

 EOL1 = b'\n\n'

 EOL2 = b'\n\r\n'

 response  = b'HTTP/1.0 200 OK\r\nDate: Mon, 1 Jan 1996 01:01:01 GMT\r\n'

 response += b'Content-Type: text/plain\r\nContent-Length: 13\r\n\r\n'

 response += b'Hello, world!'

 serversocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

 serversocket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)

 serversocket.bind(('localhost', 10000))

 serversocket.listen(1)

 serversocket.setblocking(0)

 epoll = select.epoll()

 epoll.register(serversocket.fileno(), select.EPOLLIN)

 try:

    connections = {}; requests = {}; responses = {}

    while True:

       events = epoll.poll(1)

       for fileno, event in events:

          if fileno == serversocket.fileno():

             connection, address = serversocket.accept()

             connection.setblocking(0)

             epoll.register(connection.fileno(), select.EPOLLIN)

             connections[connection.fileno()] = connection

             requests[connection.fileno()] = b''

             responses[connection.fileno()] = response

          elif event & select.EPOLLIN:

             requests[fileno] += connections[fileno].recv(1024)

             if EOL1 in requests[fileno] or EOL2 in requests[fileno]:

                epoll.modify(fileno, select.EPOLLOUT)

                print('-'*40 + '\n' + requests[fileno].decode()[:-2])

          elif event & select.EPOLLOUT:

             byteswritten = connections[fileno].send(responses[fileno])

             responses[fileno] = responses[fileno][byteswritten:]

             if len(responses[fileno]) == 0:

                epoll.modify(fileno, 0)

                connections[fileno].shutdown(socket.SHUT_RDWR)

          elif event & select.EPOLLHUP:

             epoll.unregister(fileno)

             connections[fileno].close()

             del connections[fileno]

 finally:

    epoll.unregister(serversocket.fileno())

    epoll.close()

    serversocket.close()