Python 教程 8: 标准库 (Standard Library)

Brief Tour of the Standard Library

Operating System Interface

The os module provides dozens of functions for interacting with the operating system:

import os
os.getcwd()      # Return the current working directory
'C:\\Python312'
os.chdir('/server/accesslogs')   # Change current working directory
os.system('mkdir today')   # Run the command mkdir in the system shell
0

Be sure to use the import os style instead of from os import *. This will keep os.open() from shadowing the built-in open() function which operates much differently.

File Wildcards

The glob module provides a function for making file lists from directory wildcard searches:

import glob
glob.glob('*.py')
['primes.py', 'random.py', 'quote.py']

Command Line Arguments

Common utility scripts often need to process command line arguments. These arguments are stored in the sys module’s argv attribute as a list. For instance the following output results from running python demo.py one two three at the command line:

import sys
print(sys.argv)
['demo.py', 'one', 'two', 'three']