python socket 服务器和客户端

import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
port = input("port: ")
sock.bind(('localhost', port))
print "serving on port %s" %(port)
sock.listen(1)

while 1:
    connection,address = sock.accept()
    while 1:
        print "receiving ..."
        buf = connection.recv(1024)
        if buf == '1': connection.send('welcome to server!')
        elif buf == 'shutdown': connection.close();break
        else: connection.send(buf);print buf

import socket
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
port = input("port: ")
sock.connect(('localhost', port))
while 1:
    data = raw_input("data to send: ")
    if data == "quit":
        sock.close()
        break
    sock.send(data)
    print "receiving..."
    datas = sock.recv(1024)
    print datas