Python 文件目录操作

from os import listdir
from os import getcwd
from os.path import isfile

listdir:  列出当前路径下的所有目录，文件
os.path.isfile:   判断路径是否是文件
os.path.basename: path=‘c:\aa\bb\cc’,则返回cc
getcwd, sys.modules[__name__].__file__, sys.argv[0]: 当前的工作路径

__file__: 该模块的路径，包括模块名

__name__和__main__:

'__main__' is the name of the scope in which top-level code executes. A module’s __name__ is set equal to '__main__' when read from standard input, a script, or from an interactive prompt.

A module can discover whether or not it is running in the main scope by checking its own __name__, which allows a common idiom for conditionally executing code in a module when it is run as a script or with python -m but not when it is imported:

if __name__ == "__main__":
# execute only if run as a script
main()
For a package, the same effect can be achieved by including a __main__.py module, the contents of which will be executed when the module is run with -m.

一个log处理的示例，找到目录下所有的文件中的行，改行包含字符xxx.cn，改行的上一行包含<domain:update，打印出行号

# -*-coding:utf-8 -*-

import os
from os import listdir
from os.path import isfile, join

def process_log():
curr_path = os.path.dirname(__file__)
onlyfiles = [f for f in listdir(curr_path) if isfile(join(curr_path, f))]
all_files = [os.path.join(curr_path, name) for name in onlyfiles if name.find('eppXML.log.2015') >= 0]

for one_file in all_files:
with open(one_file) as log:
lines = log.readlines()
n = 0
find_numbers = []
for line in lines:
if line.find('<domain:update') >= 0 and lines[n + 1].find('xxx.cn') >= 0:
find_numbers.append(n)
n += 1
if len(find_numbers) == 0:
continue
print '%s : %s' % (os.path.basename(one_file), find_numbers)