Python 3: Traverse Directory

By Xah Lee. Date: . Last updated: .
os.walk(input_path)
visit input_path and EVERY nested sub directory of input_path.

For each dir visit, starting with input_path, “os.walk()” returns a “generator” (a list-like thing), where each element is a tuple of this format:

  • full_path_of_dir → full path of current directory.
  • subdir_names_list → list of subdir names (not full path) that are immediate children.
  • file_name_list → list of file names (not full path) that are immediate children.

If the current dir doesn't have subdir or files, it'll be a empty list.

Note: os.walk is new in Python 3, but also available in python 2.7.x.

In older version of Python 2, you'll need to use os.path.walk. [see Python 2: Traverse Directory]

Here's a example of using os.walk to visit all files in a directory and all its subdirectories.

# Python 3

# traverse dir

import os

input_path = "/Users/xah/web/xahlee_info/python/"

for dir_path, subdir_list, file_list in os.walk(input_path):
    for fname in file_list:
        full_path = os.path.join(dir_path, fname)
        print(full_path)

# output sample:
# /Users/xah/web/xahlee_info/python/stateful_func.html
# /Users/xah/web/xahlee_info/python/function_def.html
# /Users/xah/web/xahlee_info/python/python3_traverse_dir.html
# more

Return Type of os.walk

the os.walk returns a generator object.

# Python 3

import os

print(os.walk("/home/"))
# <generator object walk at 0xb705561c>

print(type(os.walk("/home/")))
# <class 'generator'>

“generator” is like a list, but more efficient because it doesn't actually compute the result until needed. You can convert the result of generator into a list by calling list().

# Python 3

import os

print( list( os.walk("/home/") ) )
# [('/home/', [], [])]

Python Text Processing

Python

Regex

Text Processing

Web

Misc