Python Socket 编程

client:
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], '<address> <port>'
        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 == '':
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