[转]Python Socket 编程示例

老师留的作业，用Python写出来的，比C++简单的多 :-）
server端处理使用多线程，希望大家多多指教。

编写一个基于TCP的服务器与客户程序
要求服务器能同时接收5个客户的连接请求
客户从键盘接收用户的输入，在回车后将用户输入的内容发送给服务器，服务器将接收的内容发回，客户方接收后再显示在用户的显示器上（即echo功能），当服务器方接收到exit这个串时，要发回byebye这个消息，然后退出，而客户方在接收到byebye这个消息后再退出。举例如下（客户方）：
输入：hello
输出：hello
输入：enjoy socket programming!
输出：enjoy socket programming!
输入：exit
输出：byebye
服务器方的IP地址与端口要以参数的形式给出，如：
C:> tcpclient 202.118.1.60 1234

 

 tcpClient.py

import socket, sys

if __name__ == '__main__':

    #处理参数

    argv = sys.argv
    if (len(argv)!=3) or (len(argv)==2 and argv[1]=='/?'):
        print '>>>Useage:', argv[0], '

'
        sys.exit(0)

    HOST = argv[1]          #Server IP地址
    PORT = int(argv[2])     #Server 端口

    print '>>>HOST:', HOST
    print '>>>PORT:', PORT

    #打开socket
    try:
        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    except socket.error:
        print '>>>Fail to open socket!'
        sys.exit(1)

       print '>>>Socket opened...'

    #连接
    try:
        sock.connect((HOST, PORT))
    except socket.error:
        print '>>>Fail to connect!'
        sock.close()
        print '>>>Socket closed...'
        sys.exit(1)

    print '>>>Socket connected...'

   

    flag = 1            #循环标志
    iReturnValue = 0    #系统返回值

    #向Server发送信息并回显
    while(flag):
        msg = raw_input('>>>Input message: ')
    
        if msg == '':
            continue

        if msg == 'exit':
            flag = 0
      
        #发送信息
        try:
            sock.send(msg)
        except socket.error:
            print '>>>Fail to send message!'
            iReturnValue = 1
            break

        print '>>>Message sent    :', msg

        #接收信息

        try:    
            msg = sock.recv(1024)
        except socket.error:
            print '>>>Fail to receive message!'
            iReturnValue = 1
            break

        print '>>>Message received:', msg

    #关闭socket，退出程序
    sock.close()
    print '>>>Socket closed...'
    print 'Exit client program.'
    sys.exit(iReturnValue)

---------------------------------------------

tcpServer.py

import socket, threading
import sys, copy, time

iClientCount = 0 #客户端连接数

def ConnectThread(conn, addr):
    """
    Function called by thread to deal with client connection
   """

    global iClientCount         #引用全局变量
    sock = copy.copy(conn)      
    address = copy.copy(addr)

    flag = 1
    while(flag):
        try:
            msg = sock.recv(1024)
        except socket.error:
            print '>>>A \'receive\' error happened! IP:', address[0],
'PORT:', address[1]
            break
       
        if str(msg) == 'exit': 
            msg = 'byebye'
            flag = 0
        
        try:
            sock.send(msg)
        except socket.error:
            print '>>>A \'send\' error happened! IP:', address[0], 'PORT:',
address[1]
            break

    iClientCount -= 1
    print '>>>Disconnected with', address[0], 'at port', address[1] 
    print '>>>Total number of connections is', iClientCount
    sock.close()

def ListenThread(sock):
    """
    Function called by thread to listen a connection
    """

    global iClientCount

    while 1:

        if iClientCount >= MAX_CLIENTS:
            time.sleep(5)
            continue

        try:
            conn, addr = sock.accept()
        except socket.error:
            print '>>>An \'accept\' error happened!'
            continue

        iClientCount += 1
        print '>>>Connecting from', addr[0], 'at port', addr[1]
        print '>>>Total number of connections is', iClientCount
        threading.Thread(target=ConnectThread, args=(conn, addr)).start()



if __name__ == '__main__':

    argv = sys.argv
    if (len(argv)>3) or (len(argv)==2 and argv[1]=='/?'):
        print '>>>Useage:', argv[0], '[port=]
[max=]'
        sys.exit(0)
  
    HOST = ''
    PORT = 8006
    MAX_CLIENTS = 5

    for arg in argv[1:]:
        if arg.startwith('port='):
            PORT = int(arg[len('port='):])
        elif arg.startwith('max='):
            MAX_CLIENTS = int(arg[len('max='):])
 
    print '>>>PORT:', PORT
    print '>>>MAX_CLIENTS:', MAX_CLIENTS

    try:
        sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
    except socket.error:
        print 'Fail to open socket!'
        sys.exit(1)

    print '>>>Socket opened...'

    try:
        sock.bind((HOST, PORT))
    except socket.error:
        print 'Fail to bind port!'
        sock.close()
        sys.exit(1)

    print '>>>Socket binding...'

    try:
        sock.listen(MAX_CLIENTS)
    except socket.error:
        print 'Fail to listen!'
        sock.close()
        sys.exit(1)

   print '>>>Socket listening...'

    threading.Thread(target=ListenThread, args=(sock,)).start()

     #此程序不能自己结束:-)