# settings.py

HOST = ‘localhost‘
PORT = 5556
buffersize = 1024
ADDR = HOST, PORT

# server.py

import sys
from settings import *
from socket import *
from select import select

s = socket()
s.setsockopt(SOL_SOCKET, SO_REUSEADDR, 1)
s.bind(ADDR)
s.listen()

rlist = [s, sys.stdin]    # 需要等待处理的IO事件
wlist = []        # 希望主动处理的IO事件
xlist = []        # 出错后要处理的IO事件

f = open(‘text‘, ‘w‘, encoding=‘utf-8‘)

while True:
    print(‘Waiting for connection...‘)
    try:
        rs, ws, xs = select(rlist, wlist, xlist)    
    except KeyboardInterrupt:
        # 按下Ctrl+C退出程序
        print(‘KeyboardInterrupt: Ctrl+C to exit‘)
        break
    
    for r in rs:
        if r is s:
            conn, addr = s.accept()
            # 将客户端套接字加入监听列表
            rlist.append(conn)    
        elif r is sys.stdin:
            data = r.readline()
            f.write(data)
            f.flush()
        else:
            data = r.recv(buffersize)
            if not data:
                rlist.remove(r)
                r.close()
            else:
                data = data.decode()
                f.write(data)
                if not data[-1] == ‘\n‘:
                    f.write(‘\n‘)    
                f.flush()

f.close()
s.close()

print(‘El Fin‘)

# client.py

from socket import *
from settings import *

s = socket()
s.connect(ADDR)

while True:
    data = input(‘>> ‘)
    if not data:
        break
    s.send(data.encode())

s.close()