Python Directory and Files Management with OS

If there are large number of files in Python, we can place related files in different directories to make things more manageable. A directory or folder is a collection of files and sub directories. Python has the os module, which provides us with many useful methods to work with directories (and files as well).

Get Current Directory

We can get the present working directory using the getcwd() method. This method returns the current working directory in the form of a string. We can also use the getcwdb() method to get it as bytes object.

>>> import os

>>> os.getcwd()
'C:\\Program Files\\PyScripter'

>>> os.getcwdb()
b'C:\\Program Files\\PyScripter'

The extra backslash implies escape sequence. The print() function will render this properly.

>>> print(os.getcwd())
C:\Program Files\PyScripter

Changing Directory

We can change the current working directory using the chdir() method. The new path that we want to change to must be supplied as a string to this method. We can use both forward slash (/) or the backward slash (\) to separate path elements. It is safer to use escape sequence when using the backward slash.

>>> os.chdir('C:\\Python33')

>>> print(os.getcwd())
C:\Python33

List Directories and Files

All files and sub directories inside a directory can be known using the listdir() method. This method takes in a path and returns a list of sub directories and files in that path. If no path is specified, it returns from the current working directory.

>>> print(os.getcwd())
C:\Python33

>>> os.listdir()
['DLLs',
'Doc',
'include',
'Lib',
'libs',
'LICENSE.txt',
'NEWS.txt',
'python.exe',
'pythonw.exe',
'README.txt',
'Scripts',
'tcl',
'Tools']

>>> os.listdir('G:\\')
['$RECYCLE.BIN',
'Movies',
'Music',
'Photos',
'Series',
'System Volume Information']

Making a New Directory

We can make a new directory using the mkdir() method. This method takes in the path of the new directory. If the full path is not specified, the new directory is created in the current working directory.

>>> os.mkdir('test')

>>> os.listdir()
['test']

Renaming a Directory or a File

The rename() method can rename a directory or a file. The first argument is the old name and the new name must be supplies as the second argument.

>>> os.listdir()
['test']

>>> os.rename('test','new_one')

>>> os.listdir()
['new_one']

Removing Directory or File

A file can be removed (deleted) using the remove() method. Similarly, the rmdir() method removes an empty directory.

>>> os.listdir()
['new_one', 'old.txt']

>>> os.remove('old.txt')
>>> os.listdir()
['new_one']

>>> os.rmdir('new_one')
>>> os.listdir()
[]

However, note that rmdir() method can only remove empty directories. In order to remove a non-empty directory we can use the rmtree() method inside the shutil module.

>>> os.listdir()
['test']

>>> os.rmdir('test')
Traceback (most recent call last):
...
OSError: [WinError 145] The directory is not empty: 'test'

>>> import shutil

>>> shutil.rmtree('test')
>>> os.listdir()
[]