python 通过UDP传输文件

使用一个简单的python脚本将一个本地文件以码流的形式，通过UDP协议发送到对端：

import socket

import os

import stat

import struct

 

MAX_PACK_SIZE = 100

DEST_IP = 'localhost'

DEST_PORT = 17800

 

filename = raw_input("input filename")

 

filesize = os.stat(filename)[stat.ST_SIZE]

 

f = open(filename, "rb")

 

chList = []

for i in range(0, filesize):

    (ch,) = struct.unpack("B", f.read(1))

    chList.append(ch)

 

client = socket.socket( socket.AF_INET, socket.SOCK_DGRAM )

 

packSize = 0

string = ""

args = []

for i in range(0, filesize):

    packSize = packSize + 1

    string = string + struct.pack("B", chList[i])

    if (MAX_PACK_SIZE == packSize or i == filesize - 1):

        client.sendto(string, (DEST_IP, DEST_PORT))

        packSize = 0

        string = ""

client.close()

 

使用到的知识点：

1、UDP客户端最简单的实现:

client = socket.socket( socket.AF_INET, socket.SOCK_DGRAM )

client.sendto(string, (DEST_IP, DEST_PORT))

client.close()

 

2、python中对码流的操作：struct.pack 和 struct.unpack的使用

(ch,) = struct.unpack("B", f.read(1))

string = string + struct.pack("B", chList[i])

 

3、二进制文件的读取：

f = open(filename, "rb")

 

4、获得系统中某个文件的字节数

filesize = os.stat(filename)[stat.ST_SIZE]