Python 3: Traverse Directory

By Xah Lee. Date: . Last updated: .

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)

# /Users/xah/web/xahlee_info/python/about.html
# /Users/xah/web/xahlee_info/python/charset_encoding.html
# /Users/xah/web/xahlee_info/python/charset_encoding_dir.html
# ...

os.walk(input_path) will 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, subdir_names_list, file_name_list )

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

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/', [], [])]

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(). For how, see: Python: Traverse Directory

Python Text Processing

  1. Read/Write File
  2. Walk Directory
  3. File Path
  4. Process Unicode
  5. Convert File Encoding
  6. Convert File Encoding in a Dir
  7. Find Replace in dir
  8. Find Replace by Regex
  9. Count Word Frequency

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Python

  1. Python 3 Basics
  2. Python 2 Basics
  3. Python 2 and 3 Difference
  4. Print Version
  5. Builtin Help
  6. Quote String
  7. String Methods
  8. Format String
  9. Operators
  10. Complex Numbers
  11. True, False
  12. if then else
  13. Loop
  14. List Basics
  15. Loop Thru List
  16. Map f to List
  17. Copy Nested List
  18. List Comprehension
  19. List Methods
  20. Sort
  21. Dictionary
  22. Loop Thru Dict
  23. Dict Methods
  24. Tuple
  25. Sets
  26. Function
  27. Closure
  28. 2 Closure
  29. Decorator
  30. Class
  31. Object, ID, Type
  32. List Modules
  33. Write a Module
  34. Unicode 🐍

Regex

  1. Regex Basics
  2. Regex Reference

Text Processing

  1. Read/Write File
  2. Traverse Directory
  3. File Path
  4. Process Unicode
  5. Convert File Encoding
  6. Find Replace in dir
  7. Find Replace by Regex
  8. Count Word Frequency

Web

  1. Send Email
  2. GET Web Page
  3. Web Crawler
  4. HTTP POST

Misc

  1. JSON
  2. Find Script Path
  3. Get Env Var
  4. System Call
  5. Decompress Gzip
  6. Append String in Loop
  7. Timing f timeit
  8. Keyword Arg Default Value Unstable
  9. Check Page Load Size
  10. Thumbnail Generation