python 文件操作的小实例

[root@vps616 python]# cat main.py 
#python2.7.3
#coding=utf8

import os
import sys

def sub_directory(path, old, new):
    path_set = []

    for dirpath, dirnames, filenames in os.walk(path):
        for name in filenames:
            full_path = os.path.join(dirpath, name)
            full_path = full_path.replace(old, new)
            path_set.append(full_path)
            
    return path_set

if __name__ == "__main__":
    print sub_directory(sys.argv[1], sys.argv[2], sys.argv[3])

import os

properties = open("text.txt",'rb+')
lines = properties.readlines()
d=""
for line in lines:
    c = line.replace("my name is abc", "my name is efg")
    d += c
    properties.seek(0)      #不要让python记住执行到这里，从文件头还始
    properties.truncate()   #清空文件
    properties.write(d)
    properties.close()