一、什么是socket？
Python 官方关于 Socket 的函数请看 http://docs.python.org/library/socket.html
socket通常也称作"套接字"，用于描述IP地址和端口，是一个通信链的句柄，应用程序通常通过"套接字"向网络发出请求或者应答网络请求。
socket起源于Unix，而Unix/Linux基本哲学之一就是“一切皆文件”，对于文件用打开、读写、关闭模式来操作。socket就是该模式的一个实现，socket即是一种特殊的文件，一些socket函数就是对其进行的操作（读/写IO、打开、关闭）
file模块是针对某个指定文件进行打开、读写、关闭
socket模块是针对 服务器端 和 客户端Socket 进行打开、读写、关闭
二、举个实例
1 #!/usr/bin/env python 2 # _*_ coding: UTF-8 _*_ 3 # Author:taoke 4 import socket 5 import sys 6 try: 7 #创建socket 8 s = socket.socket(socket.AF_INET,socket.SOCK_STREAM) 9 except socket.error: 10 #创建失败，产生socket.error异常 11 print("socket creat error:"+str(socket.error)) 12 sys.exit() 13 14 print("creat socket") 15 host = 'www.oschina.net' 16 17 try: 18 #获取主机IP 19 remote_ip = socket.gethostbyname(host) 20 except socket.gaierror: 21 print("hostname could not be resolved,exiting") 22 sys.exit() 23 print("IP address of "+host+" is "+remote_ip) 24 port = 80 25 #连接 26 s.connect((remote_ip,port)) 27 print('Socket Connected to ' + host + ' on ip ' + remote_ip) 28 #Send some data to remote server 29 message = "GET / HTTP/1.1 Host: oschina.net " 30 31 try : 32 #Set the whole string 33 s.sendall(message.encode()) 34 except socket.error: 35 #Send failed 36 print('Send failed') 37 sys.exit() 38 39 print('Message send successfully') 40 41 #Now receive data 42 reply = s.recv(4096) 43 44 print(reply.decode()) 45 #关闭socket 46 s.close()
运行结果如下：
creat socket IP address of www.oschina.net is 139.199.91.153 Socket Connected to www.oschina.net on ip 139.199.91.153 Message send successfully HTTP/1.1 301 Moved Permanently X-Proxy: dayu-proxy Date: Wed, 20 Sep 2017 13:28:07 GMT Content-Type: text/html Content-Length: 278 X-DAYU-UUID: D7PRC9C6CFCF6932495F893F61E66ABDB60C Connection: keep-alive Set-Cookie: __DAYU_PP=733na7yMm7VYJ7VbeQz3ffffffffef192cb9ef6a; Expires=Wed, 09 Jun 2021 23:59:59 GMT; Path=/ Location: http://www.oschina.net/ <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN"> <html> <head><title>301 Moved Permanently</title></head> <body bgcolor="white"> <h1>301 Moved Permanently</h1> <p>The requested resource has been assigned a new permanent URI.</p> <hr/>Powered by Tengine</body> </html>
TCP客户端:
1 创建套接字，连接远端地址
# socket.socket(socket.AF_INET,socket.SOCK_STREAM) , s.connect()
2 连接后发送数据和接收数据
# s.sendall(), s.recv()
3 传输完毕后，关闭套接字
#s.close()