Python客户端与服务端的简单网络编程示例

本文实例讲述了Python简单网络编程。分享给大家供大家参考，具体如下：

内容目录

1. 客户端（client.py）
2. 服务端（server.py）

一、客户端（client.py）

import socket
import sys
port = 70
host = sys.argv[1]
filename = sys.argv[2]
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((host, port))
fd = s.makefile("rw", 0)
fd.write(filename + "
")
for line in fd.readlines():
 sys.stdout.write(line)

程序通过socket.socket()建立一个Socket，参数告诉系统需要一个Internet Socket进行TCP通信。接着程序链接远程的主机名，并提供文件名。最后获得响应后在屏幕上打印出来。

测试

python client.py quux.org /

显示

iWelcome to gopher at quux.org! fake (NULL) 0
i fake (NULL) 0
iThis server has a lot of information of historic interest, fake (NULL) 0
ifunny, or just plain entertaining -- all presented in Gopher. fake (NULL) 0
iThere are many mirrors here of rare or valuable files with the fake (NULL) 0
iaim to preserve them in case their host disappears. PLEASE READ fake (NULL) 0
i"About This Server" FOR IMPORTANT NOTES AND LEGAL INFORMATION. fake (NULL) 0
i fake (NULL) 0
0About This Server /About This Server.txt gopher.quux.org 70 +
1Archives /Archives gopher.quux.org 70 +
1Books /Books gopher.quux.org 70 +
1Communication /Communication gopher.quux.org 70 +
iThis directory contains the entire text of the book fake (NULL) 0
i"We the Media: Grassroots Journalism by the People, for the People" fake (NULL) 0
iby Dan Gillmor in various formats. fake (NULL) 0
i fake (NULL) 0
iFeel free to download and enjoy. fake (NULL) 0
1Computers /Computers gopher.quux.org 70 +
1Current Issues and Events (Updated Apr. 23, 2002) /Current gopher.quux.org 70 +
1Development Projects /devel gopher.quux.org 70 +
0Gopher's 10th Anniversary /3.0.0.txt gopher.quux.org 70
1Government, Politics, Law, and Conflict /Government gopher.quux.org 70 +
0How To Help /How To Help.txt gopher.quux.org 70 +
1Humor and Fun /Humor and Fun gopher.quux.org 70 +
1Index to Quux.Org /Archives/index gopher.quux.org 70
1Internet /Internet gopher.quux.org 70 +
1Other Gopher Servers /Software/Gopher/servers gopher.quux.org 70
1People /People gopher.quux.org 70 +
1Reference /Reference gopher.quux.org 70 +
1Software and Downloads /Software gopher.quux.org 70 +
1The Gopher Project /Software/Gopher gopher.quux.org 70
0What's New /whatsnew.txt gopher.quux.org 70 +　

二、服务端（server.py）

# coding: utf-8
import socket
host = ''
port = 51421
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind((host, port))
s.listen(1) #每次最多只有一个等候处理
print "Server is running on port %d; press Ctrl-C to terminate." %port
while 1:
 clientsock, clientaddr = s.accept()
 clientfile = clientsock.makefile('rw', 0)
 clientfile.write("Welcome, " + str(clientaddr) + "
")
 clientfile.write("Please enter a string: ")
 line = clientfile.readline().strip()
 clientfile.write("You entered %d characters. 
" %len(line))
 clientfile.close()
 clientsock.close()

建立一个socket，设置成可复用的（reusable），绑定端口号51421（可选大于1024的任一值），调用listen（）函数，开始等待来自客户端的请求，同时设定最多只有一个等候处理的链接。

主循环对a.accept（）函数调用开始，程序连接一个客户端后立马停止，接收用户的输入。

运行一个例子

首先运行server.py

python server.py

另开一个终端，连接localhost的51421端口。　

jihite@ubuntu:~/web$ telnet localhost 51421
Trying 127.0.0.1...
Connected to localhost.
Escape character is '^]'.
Welcome, ('127.0.0.1', 59853)
Please enter a string: mm
You entered 2 characters.
Connection closed by foreign host.