1.重用套接字地址：

# -*- coding: UTF-8 -*-
# 如果在某个端口上运行一个Python套接字服务器，连接一次后便终止了运行，就不能在使用这个端口了
# !usr/bin/env python
# Python Network Programming Cookbook --Chapter -1
# This program is optimized for Python 2.7
# It may run on any other version with/without modifications

import socket
import sys

def reuse_socket_addr():
    sock=socket.socket(socket.AF_INET,socket.SOCK_STREAM)

    old_state=sock.getsockopt(socket.SOL_SOCKET,socket.SO_REUSEADDR)
    print "旧的套接字状态是:%s" %old_state

    sock.setsockopt(socket.SOL_SOCKET,socket.SO_REUSEADDR,1)
    new_state=sock.getsockopt(socket.SOL_SOCKET,socket.SO_REUSEADDR)
    print "新的套接字状态是:%s" %new_state

    local_port=8282

    srv=socket.socket(socket.AF_INET,socket.SOCK_STREAM)
    srv.setsockopt(socket.SOL_SOCKET,socket.SO_REUSEADDR,1)
    srv.bind((‘‘,local_port))
    srv.listen(1)
    print "监听端口是：%s"%local_port

    while True:
        try:
            connection,addr=srv.accept()
            print "连接是被%s" %(addr[0],addr[1])
        except KeyboardInterrupt:
            break
        except socket.error,msg:
            print ‘%s‘ %(msg,)


if __name__==‘__main__‘:
    reuse_socket_addr()

2.从网络时间服务器获取并打印当前时间：

# -*- coding: UTF-8 -*-
# 很多程序要求设备的时间准确，设备上的时间可能不够准确，需要和网络中的时间服务器同步，
# 编写一个Python客户端，让设备上的时间和某个网络服务器同步，要完成这一步骤，需要使用ntplib，
# 通过网络时间协议，即NTP处理客户端和服务器之间的通信，pip install ntplib
# !usr/bin/env python
# Python Network Programming Cookbook --Chapter -1
# This program is optimized for Python 2.7
# It may run on any other version with/without modifications

import ntplib
from time import ctime

def print_time():
    ntp_client=ntplib.NTPClient()
    response=ntp_client.request(‘cn.pool.ntp.org‘)
    print ctime(response.tx_time)

if __name__==‘__main__‘:
    print_time()

3.编写一个SNTP客户端（简单网络时间协议）:

# -*- coding: UTF-8 -*-
# 有时不需要从NTP服务器上获取精确的时间，可以使用NTP的简化版，简单网络时间协议
# !usr/bin/env python
# Python Network Programming Cookbook --Chapter -1
# This program is optimized for Python 2.7
# It may run on any other version with/without modifications

import socket
import struct
import sys
import time

NTP_SERVER="0.cn.pool.ntp.org"
TIME1970=2208988800L

def sntp_client():
    client=socket.socket(socket.AF_INET,socket.SOCK_DGRAM)
    data=http://www.mamicode.com/‘/x1b‘+47*‘/0‘
    client.sendto(data,(NTP_SERVER,123))
    data,address=client.recvfrom(1024)

    if data:
        print ‘接收数据来自:‘,address
    t=struct.unpack(‘!12I‘,data)[10]
    t-=TIME1970
    print ‘\t时间是:%s‘%time.ctime(t)

if __name__==‘__main__‘:
    sntp_client()

4.编写一个简单的回显客户端/服务器应用：

服务器程序：

# -*- coding: UTF-8 -*-
# 这个例子中，不管服务器从客户端收到什么输入，都会将其回显出来，
# 使用Python中的argparse模块，在命令行指定TCP端口服务器脚本和客户端脚本都要用到这个参数
# !usr/bin/env python
# Python Network Programming Cookbook --Chapter -1
# This program is optimized for Python 2.7
# It may run on any other version with/without modifications

import socket
import sys
import argparse

host=‘localhost‘
data_payload=2048
backlog=5


def echo_server(port):
    """一个简单的回显服务器应用"""
    sock=socket.socket(socket.AF_INET,socket.SOCK_STREAM)

    sock.setsockopt(socket.SOL_SOCKET,socket.SO_REUSEADDR,1)
    server_address=(host,port)
    print "Starting up echo server on %s port %s" %server_address

    sock.bind(server_address)
    sock.listen(backlog)
    port=int(port)
    while True:
        print "等待接收信息从Client"
        client,address=sock.accept()
        data=http://www.mamicode.com/client.recv(data_payload)
        if data:
            print "Data:%s" %data
            print "发送%s 字节 返回给%s" %(data,address)
            client.send(data)
        client.close()

if __name__==‘__main__‘:
    parser=argparse.ArgumentParser(description=‘Socket Server Example‘)
    parser.add_argument(‘--port‘,action="store",dest="port",type=int,required=True)
    given_args=parser.parse_args()
    port=given_args.port

    echo_server(port)

客户端程序：

# -*- coding: UTF-8 -*-
# 这个例子中，不管服务器从客户端收到什么输入，都会将其回显出来，
# 使用Python中的argparse模块，在命令行指定TCP端口服务器脚本和客户端脚本都要用到这个参数
# !usr/bin/env python
# Python Network Programming Cookbook --Chapter -1
# This program is optimized for Python 2.7
# It may run on any other version with/without modifications

import socket
import sys

import argparse

host=‘localhost‘

def echo_client(port):
    """一个简单的回显消息的客户端"""
    sock=socket.socket(socket.AF_INET,socket.SOCK_STREAM)
    server_address=(host,port)

    print "连接到服务器%s 的端口%s" %server_address
    sock.connect(server_address)

    try:
        message="Test message.This is will be echoed"
        print "发送消息%s" % message
        sock.sendall(message)


        amount_received = 0
        amount_excepeted = len(message)
        while amount_received < amount_excepeted:

            data=http://www.mamicode.com/sock.recv(1024)

            print len(data)

            amount_received+=len(data)
            print amount_received
            print "Received data:%s" % data

    except socket.errno,e:
        print "Socket Error：%s" %str(e)

    except Exception,e:
        print "other exception: %s" %str(e)

    finally:
        print "Closeing Connection to the server"
        sock.close()



if __name__==‘__main__‘:
    parser=argparse.ArgumentParser(description=‘套接字服务案例‘)
    parser.add_argument(‘--port‘,action="store",dest="port",type=int,required=True)
    given_args=parser.parse_args()
    port=given_args.port
    echo_client(port)

对python Socket的详细讲解：

2017.07.09 Python网络编程之重用套接字地址