How can I list all files of a directory in Python and add them to a list?

import os
os.listdir("somedirectory")

will return a list of all files and directories in "somedirectory".

os.listdir() will get you everything that's in a directory - files and directories.

If you want just files, you could either filter this down using os.path:

from os import listdir
from os.path import isfile, join
onlyfiles = [f for f in listdir(mypath) if isfile(join(mypath, f))]

or you could use os.walk() which will yield two lists for each directory it visits - splitting into files and dirs for you. If you only want the top directory you can just break the first time it yields

from os import walk

f = []
for (dirpath, dirnames, filenames) in walk(mypath):
    f.extend(filenames)
    break

And lastly, as that example shows, adding one list to another you can either use .extend() or

>>> q = [1, 2, 3]
>>> w = [4, 5, 6]
>>> q = q + w
>>> q
[1, 2, 3, 4, 5, 6]

Personally, I prefer .extend()

I prefer using the glob module, as it does pattern matching and expansion.

import glob
print(glob.glob("/home/adam/*.txt"))

It will return a list with the queried files:

['/home/adam/file1.txt', '/home/adam/file2.txt', .... ]

import dircache
list = dircache.listdir(pathname)
i = 0
check = len(list[0])
temp = []
count = len(list)
while count != 0:
  if len(list[i]) != check:
     temp.append(list[i-1])
     check = len(list[i])
  else:
    i = i + 1
    count = count - 1

print temp

Getting Full File Paths From a Directory and All Its Subdirectories

import os

def get_filepaths(directory):
    """
    This function will generate the file names in a directory 
    tree by walking the tree either top-down or bottom-up. For each 
    directory in the tree rooted at directory top (including top itself), 
    it yields a 3-tuple (dirpath, dirnames, filenames).
    """
    file_paths = []  # List which will store all of the full filepaths.

    # Walk the tree.
    for root, directories, files in os.walk(directory):
        for filename in files:
            # Join the two strings in order to form the full filepath.
            filepath = os.path.join(root, filename)
            file_paths.append(filepath)  # Add it to the list.

    return file_paths  # Self-explanatory.

# Run the above function and store its results in a variable.   
full_file_paths = get_filepaths("/Users/johnny/Desktop/TEST")

• The path I provided in the above function contained 3 files— two of them in the root directory, and another in a subfolder called "SUBFOLDER." You can now do things like:

• print full_file_paths which will print the list:

  • ['/Users/johnny/Desktop/TEST/file1.txt', '/Users/johnny/Desktop/TEST/file2.txt', '/Users/johnny/Desktop/TEST/SUBFOLDER/file3.dat']

If you'd like, you can open and read the contents, or focus only on files with the extension ".dat" like in the code below:

for f in full_file_paths:
  if f.endswith(".dat"):
    print f

/Users/johnny/Desktop/TEST/SUBFOLDER/file3.dat

A one-line solution to get only list of files (no subdirectories):

filenames = next(os.walk(path))[2]

or absolute pathnames:

paths = [os.path.join(path,fn) for fn in next(os.walk(path))[2]]

# -** coding: utf-8 -*-
import os
import traceback

print '\n\n'

def start():
    address = "/home/ubuntu/Desktop"
    try:
        Folders = []
        Id = 1
        for item in os.listdir(address):
            endaddress = address + "/" + item
            Folders.append({'Id': Id, 'TopId': 0, 'Name': item, 'Address': endaddress })
            Id += 1         

            state = 0
            for item2 in os.listdir(endaddress):
                state = 1
            if state == 1: 
                Id = FolderToList(endaddress, Id, Id - 1, Folders)
        return Folders
    except:
        print "___________________________ ERROR ___________________________\n" + traceback.format_exc()

def FolderToList(address, Id, TopId, Folders):
    for item in os.listdir(address):
        endaddress = address + "/" + item
        Folders.append({'Id': Id, 'TopId': TopId, 'Name': item, 'Address': endaddress })
        Id += 1

        state = 0
        for item in os.listdir(endaddress):
            state = 1
        if state == 1: 
            Id = FolderToList(endaddress, Id, Id - 1, Folders)
    return Id

print start()

If you are looking for a Python implementation of find, this is a recipe I use rather frequently:

from findtools.find_files import (find_files, Match)

# Recursively find all *.sh files in **/usr/bin**
sh_files_pattern = Match(filetype='f', name='*.sh')
found_files = find_files(path='/usr/bin', match=sh_files_pattern)

for found_file in found_files:
    print found_file

So I made a PyPI package out of it and there is also a GitHub repository. I hope that someone finds it potentially useful for this code.

def list_files(path):
    # returns a list of names (with extension, without full path) of all files 
    # in folder path
    files = []
    for name in os.listdir(path):
        if os.path.isfile(os.path.join(path, name)):
            files.append(name)
    return files 

Returning a list of absolute filepaths, does not recurse into subdirectories

L = [os.path.join(os.getcwd(),f) for f in os.listdir('.') if os.path.isfile(os.path.join(os.getcwd(),f))]

I really liked adamk's answer, suggesting that you use glob(), from the module of the same name. This allows you to have pattern matching with *s.

But as other people pointed out in the comments, glob() can get tripped up over inconsistent slash directions. To help with that, I suggest you use the join() and expanduser() functions in the os.path module, and perhaps the getcwd() function in the os module, as well.

As examples:

from glob import glob

# Return everything under C:\Users\admin that contains a folder called wlp.
glob('C:\Users\admin\*\wlp')

The above is terrible - the path has been hardcoded and will only ever work on Windows between the drive name and the \s being hardcoded into the path.

from glob    import glob
from os.path import join

# Return everything under Users, admin, that contains a folder called wlp.
glob(join('Users', 'admin', '*', 'wlp'))

The above works better, but it relies on the folder name Users which is often found on Windows and not so often found on other OSs. It also relies on the user having a specific name, admin.

from glob    import glob
from os.path import expanduser, join

# Return everything under the user directory that contains a folder called wlp.
glob(join(expanduser('~'), '*', 'wlp'))

This works perfectly across all platforms.

Another great example that works perfectly across platforms and does something a bit different:

from glob    import glob
from os      import getcwd
from os.path import join

# Return everything under the current directory that contains a folder called wlp.
glob(join(getcwd(), '*', 'wlp'))

Hope these examples help you see the power of a few of the functions you can find in the standard Python library modules.

Since version 3.4 there are builtin iterators for this which are a lot more efficient than os.listdir():

pathlib: New in version 3.4.

>>> import pathlib
>>> [p for p in pathlib.Path('.').iterdir() if p.is_file()]

According to PEP 428, the aim of the pathlib library is to provide a simple hierarchy of classes to handle filesystem paths and the common operations users do over them.

os.scandir(): New in version 3.5.

>>> import os
>>> [entry for entry in os.scandir('.') if entry.is_file()]

Note that os.walk() uses os.scandir() instead of os.listdir() from version 3.5, and its speed got increased by 2-20 times according to PEP 471.

Let me also recommend reading ShadowRanger's comment below.

import os
lst=os.listdir(path)

os.listdir returns a list containing the names of the entries in the directory given by path.

List all files in a directory:

import os
from os import path

files = [x for x in os.listdir(directory_path) if path.isfile(directory_path+os.sep+x)]

Here, you get list of all files in a directory.

Python 3.5 introduced a new, faster method for walking through the directory - os.scandir().

Example:

for file in os.scandir('/usr/bin'):
    line = ''
    if file.is_file():
        line += 'f'
    elif file.is_dir():
        line += 'd'
    elif file.is_symlink():
        line += 'l'
    line += '\t'
    print("{}{}".format(line, file.name))

If you care about performance, try scandir. For Python 2.x, you may need to install it manually. Examples:

# python 2.x
import scandir
import sys

de = scandir.scandir(sys.argv[1])
while 1:
    try:
        d = de.next()
        print d.path
    except StopIteration as _:
        break

This saves a lot of time when you need to scan a huge directory, and you do not need to buffer a huge list, just fetch one by one. And also you can do it recursively:

def scan_path(path):
    de = scandir.scandir(path)
    while 1:
        try:
            e = de.next()
            if e.is_dir():
                scan_path(e.path)
            else:
                print e.path
        except StopIteration as _:
                break

You should use os module for listing directory content.os.listdir(".") returns all the contents of the directory. We iterate over the result and append to the list.

import os

content_list = []

for content in os.listdir("."): # "." means current directory
    content_list.append(content)

print content_list

By using os library.

import os
for root, dirs,files in os.walk("your dir path", topdown=True):
    for name in files:
        print(os.path.join(root, name))

Use this function if you want to use a different file type or get the full directory:

import os

def createList(foldername, fulldir = True, suffix=".jpg"):
    file_list_tmp = os.listdir(foldername)
    #print len(file_list_tmp)
    file_list = []
    if fulldir:
        for item in file_list_tmp:
            if item.endswith(suffix):
                file_list.append(os.path.join(foldername, item))
    else:
        for item in file_list_tmp:
            if item.endswith(suffix):
                file_list.append(item)
    return file_list

Using generators

import os
def get_files(search_path):
     for (dirpath, _, filenames) in os.walk(search_path):
         for filename in filenames:
             yield os.path.join(dirpath, filename)
list_files = get_files('.')
for filename in list_files:
    print(filename)

Get a list of files with Python 2 and 3

I have also made a short video here: Python: how to get a list of file in a directory

os.listdir()

or..... how to get all the files (and directories) in current directory (Python 3)

The simplest way to have the file in the current directory in Python 3 is this. It's really simple; use the os module and the listdir() function and you'll have the file in that directory (and eventual folders that are in the directory, but you will not have the file in the subdirectory, for that you can use walk - I will talk about it later).

>>> import os
>>> arr = os.listdir()
>>> arr
['$RECYCLE.BIN', 'work.txt', '3ebooks.txt', 'documents']

Using glob

I found glob easier to select file of the same type or with something in common. Look at the following example:

import glob

txtfiles = []
for file in glob.glob("*.txt"):
    txtfiles.append(file)

Using list comprehension

import glob

mylist = [f for f in glob.glob("*.txt")]

Getting the full path name with os.path.abspath

As you noticed, you don't have the full path of the file in the code above. If you need to have the absolute path, you can use another function of the os.path module called _getfullpathname, putting the file that you get from os.listdir() as an argument. There are other ways to have the full path, as we will check later (I replaced, as suggested by mexmex, _getfullpathname with abspath).

>>> import os
>>> files_path = [os.path.abspath(x) for x in os.listdir()]
>>> files_path
['F:\\documenti\applications.txt', 'F:\\documenti\collections.txt']

Get the full path name of a type of file into all subdirectories with walk

I find this very useful to find stuff in many directories, and it helped me finding a file about which I didn't remember the name:

import os

# Getting the current work directory (cwd)
thisdir = os.getcwd()

# r=root, d=directories, f = files
for r, d, f in os.walk(thisdir):
    for file in f:
        if ".docx" in file:
            print(os.path.join(r, file))

os.listdir(): get files in the current directory (Python 2)

In Python 2 you, if you want the list of the files in the current directory, you have to give the argument as '.' or os.getcwd() in the os.listdir method.

>>> import os
>>> arr = os.listdir('.')
>>> arr
['$RECYCLE.BIN', 'work.txt', '3ebooks.txt', 'documents']

To go up in the directory tree

>>> # Method 1
>>> x = os.listdir('..')

# Method 2
>>> x= os.listdir('/')

Get files: os.listdir() in a particular directory (Python 2 and 3)

>>> import os
>>> arr = os.listdir('F:\\python')
>>> arr
['$RECYCLE.BIN', 'work.txt', '3ebooks.txt', 'documents']

Get files of a particular subdirectory with os.listdir()

import os

x = os.listdir("./content")

os.walk('.') - current directory

>>> import os
>>> arr = next(os.walk('.'))[2]
>>> arr
['5bs_Turismo1.pdf', '5bs_Turismo1.pptx', 'esperienza.txt']

glob module - all files

import glob
print(glob.glob("*"))

out:['content', 'start.py']

next(os.walk('.')) and os.path.join('dir','file')

>>> import os
>>> arr = []
>>> for d,r,f in next(os.walk("F:\_python")):
>>>     for file in f:
>>>         arr.append(os.path.join(r,file))
...
>>> for f in arr:
>>>     print(files)

>output

F:\\_python\\dict_class.py
F:\\_python\\programmi.txt

next(os.walk('F:\') - get the full path - list comprehension

>>> [os.path.join(r,file) for r,d,f in next(os.walk("F:\\_python")) for file in f]
['F:\\_python\\dict_class.py', 'F:\\_python\\programmi.txt']

os.walk - get full path - all files in sub dirs

x = [os.path.join(r,file) for r,d,f in os.walk("F:\\_python") for file in f]

>>>x
['F:\\_python\\dict.py', 'F:\\_python\\progr.txt', 'F:\\_python\\readl.py']

os.listdir() - get only txt files

>>> arr_txt = [x for x in os.listdir() if x.endswith(".txt")]
>>> print(arr_txt)
['work.txt', '3ebooks.txt']

glob - get only txt files

>>> import glob
>>> x = glob.glob("*.txt")
>>> x
['ale.txt', 'alunni2015.txt', 'assenze.text.txt', 'text2.txt', 'untitled.txt']

Using glob to get the full path of the files

If I should need the absolute path of the files:

>>> from path import path
>>> from glob import glob
>>> x = [path(f).abspath() for f in glob("F:\*.txt")]
>>> for f in x:
...  print(f)
...
F:\acquistionline.txt
F:\acquisti_2018.txt
F:\bootstrap_jquery_ecc.txt

Other use of glob

If I want all the files in the directory:

>>> x = glob.glob("*")

Using os.path.isfile to avoid directories in the list

import os.path
listOfFiles = [f for f in os.listdir() if os.path.isfile(f)]
print(listOfFiles)

> output

['a simple game.py', 'data.txt', 'decorator.py']

Using pathlib from (Python 3.4)

import pathlib

>>> flist = []
>>> for p in pathlib.Path('.').iterdir():
...  if p.is_file():
...   print(p)
...   flist.append(p)
...
error.PNG
exemaker.bat
guiprova.mp3
setup.py
speak_gui2.py
thumb.PNG

If you want to use list comprehension

>>> flist = [p for p in pathlib.Path('.').iterdir() if p.is_file()]

*You can use also just pathlib.Path() instead of pathlib.Path(".")

Use glob method in pathlib.Path()

import pathlib

py = pathlib.Path().glob("*.py")
for file in py:
    print(file)

output:

stack_overflow_list.py
stack_overflow_list_tkinter.py

Get all and only files with os.walk

import os
x = [i[2] for i in os.walk('.')]
y=[]
for t in x:
    for f in t:
        y.append(f)

>>> y
['append_to_list.py', 'data.txt', 'data1.txt', 'data2.txt', 'data_180617', 'os_walk.py', 'READ2.py', 'read_data.py', 'somma_defaltdic.py', 'substitute_words.py', 'sum_data.py', 'data.txt', 'data1.txt', 'data_180617']

Get only files with next and walk in a directory

>>> import os
>>> x = next(os.walk('F://python'))[2]
>>> x
['calculator.bat','calculator.py']

Get only directories with next and walk in a directory

>>> import os
>>> next(os.walk('F://python'))[1] # for the current dir use ('.')
['python3','others']

Get all the subdir names with walk

>>> for r,d,f in os.walk("F:\_python"):
...  for dirs in d:
...   print(dirs)
...
.vscode
pyexcel
pyschool.py
subtitles
_metaprogramming
.ipynb_checkpoints

os.scandir() from Python 3.5 on

>>> import os
>>> x = [f.name for f in os.scandir() if f.is_file()]
>>> x
['calculator.bat','calculator.py']

# Another example with scandir (a little variation from docs.python.org)
# This one is more efficient than os.listdir.
# In this case, it shows the files only in the current directory
# where the script is executed.

>>> import os
>>> with os.scandir() as i:
...  for entry in i:
...   if entry.is_file():
...    print(entry.name)
...
ebookmaker.py
error.PNG
exemaker.bat
guiprova.mp3
setup.py
speakgui4.py
speak_gui2.py
speak_gui3.py
thumb.PNG
>>>

Ex. 1: How many files are there in the subdirectories?

In this example, we look for the number of files that are included in all the directory and its subdirectories.

import os

def count(dir, counter=0):
    "returns number of files in dir and subdirs"
    for pack in os.walk(dir):
        for f in pack[2]:
            counter += 1
    return dir + " : " + str(counter) + "files"

print(count("F:\\python"))

> output

>'F:\\\python' : 12057 files'

Ex.2: How to copy all files from a directory to another?

A script to make order in your computer finding all files of a type (default: pptx) and copying them in a new folder.

import os
import shutil
from path import path

destination = "F:\\file_copied"
# os.makedirs(destination)

def copyfile(dir, filetype='pptx', counter=0):
    "Searches for pptx (or other - pptx is the default) files and copies them"
    for pack in os.walk(dir):
        for f in pack[2]:
            if f.endswith(filetype):
                fullpath = pack[0] + "\\" + f
                print(fullpath)
                shutil.copy(fullpath, destination)
                counter += 1
    if counter > 0:
        print("------------------------")
        print("\t==> Found in: `" + dir + "` : " + str(counter) + " files\n")

for dir in os.listdir():
    "searches for folders that starts with `_`"
    if dir[0] == '_':
        # copyfile(dir, filetype='pdf')
        copyfile(dir, filetype='txt')


> Output

_compiti18\Compito Contabilità 1\conti.txt
_compiti18\Compito Contabilità 1\modula4.txt
_compiti18\Compito Contabilità 1\moduloa4.txt
------------------------
==> Found in: `_compiti18` : 3 files

Ex. 3: How to get all the files in a txt file

In case you want to create a txt file with all the file names:

import os
mylist = ""
with open("filelist.txt", "w", encoding="utf-8") as file:
    for eachfile in os.listdir():
        mylist += eachfile + "\n"
    file.write(mylist)

Example: txt with all the files of an hard drive

"""We are going to save a txt file with all the files in your directory.
We will use the function walk()

"""

import os

# see all the methods of os
# print(*dir(os), sep=", ")
listafile = []
percorso = []
with open("lista_file.txt", "w", encoding='utf-8') as testo:
    for root, dirs, files in os.walk("D:\\"):
        for file in files:
            listafile.append(file)
            percorso.append(root + "\\" + file)
            testo.write(file + "\n")
listafile.sort()
print("N. of files", len(listafile))
with open("lista_file_ordinata.txt", "w", encoding="utf-8") as testo_ordinato:
    for file in listafile:
        testo_ordinato.write(file + "\n")

with open("percorso.txt", "w", encoding="utf-8") as file_percorso:
    for file in percorso:
        file_percorso.write(file + "\n")

os.system("lista_file.txt")
os.system("lista_file_ordinata.txt")
os.system("percorso.txt")

All the file of C:\\ in one text file

This is a shorter version of the previous code. Change the folder where to start finding the files if you need to start from another position. This code generate a 50 mb on text file on my computer with something less then 500.000 lines with files with the complete path.

import os

with open("file.txt", "w", encoding="utf-8") as filewrite:
    for r, d, f in os.walk("C:\\"):
        for file in f:
            filewrite.write(f"{r + file}\n")    

A function to search for a certain type of file

import os

def searchfiles(extension='.ttf'):
    "Create a txt file with all the file of a type"
    with open("file.txt", "w", encoding="utf-8") as filewrite:
        for r, d, f in os.walk("C:\\"):
            for file in f:
                if file.endswith(extension):
                    filewrite.write(f"{r + file}\n")

# looking for ttf file (fonts)
searchfiles('ttf')

import os 
os.listdir(path)

This will return a list of all files and directories in path.

filenames = next(os.walk(path))[2]

This will return only a list of files, not subdirectories.

Referring to the answer by @adamk, here is my os detection method in response to the slash inconsistency comment by @Anti Earth

import sys
import os
from pathlib import Path
from glob import glob
platformtype = sys.platform
if platformtype == 'win32':
    slash = "\\"
if platformtype == 'darwin':
    slash = "/"

# TODO: How can I list all files of a directory in Python and add them to a list?

# Step 1 - List all files of a directory

# Method 1: Find only pre-defined filetypes (.txt) and no subfiles, answer provided by @adamk
dir1 = "%sfoo%sbar%s*.txt" % (slash)
_files = glob(dir1)

# Method 2: Find all files and no subfiles
dir2 = "%sfoo%sbar%s" % (slash)
_files = (x for x in Path("dir2").iterdir() if x.is_file())

# Method 3: Find all files and all subfiles
dir3 = "%sfoo%sbar" % (slash)
_files = (x for x in Path('dir3').glob('**/*') if x.is_file())


# Step 2 - Add them to a list

files_list = []
for eachfiles in _files:
    files_basename = os.path.basename(eachfiles)
    files_list.append(files_basename)

print(files_list)
['file1.txt', 'file2.txt', .... ]

I'm assuming that you want just the basenames in the list.

Refer to this post for pre-defining multiple file formats for Method 1.

I will provide a sample one liner where sourcepath and file type can be provided as input. The code returns a list of filenames with csv extension. Use . in case all files needs to be returned. This will also recursively scans the subdirectories.

[y for x in os.walk(sourcePath) for y in glob(os.path.join(x[0], '*.csv'))]

Modify file extensions and source path as needed.

Part One ¹

Preliminary notes

• Although there's a clear differentiation between file and directory terms in the question text, some may argue that directories are actually special files
• The statement: "all files of a directory" can be interpreted in two ways:
  1. All direct (or level 1) descendants only
  2. All descendants in the whole directory tree (including the ones in sub-directories)

• When the question was asked, I imagine that Python 2, was the LTS version, however the code samples will be run by Python 3(.5) (I'll keep them as Python 2 compliant as possible; also, any code belonging to Python that I'm going to post, is from v3.5.4 - unless otherwise specified). That has consequences related to another keyword in the question: "add them into a list":

  • In pre Python 2.2 versions, sequences (iterables) were mostly represented by lists (tuples, sets, ...)
  • In Python 2.2, the concept of generator ([Python]: Generators) - courtesy of [Python]: The yield statement) - was introduced. As time passed, generator counterparts started to appear for functions that returned/worked with lists
  • In Python 3, generator is the default behavior
  • Now, I don't know if returning a list is still mandatory (or a generator would do as well), but passing a generator to the list constructor, will create a list out of it (and also consume it). The example below illustrates the differences on [Python]: map(function, iterable, ...)

  Python 2.7.10 (default, Mar  8 2016, 15:02:46) [MSC v.1600 64 bit (AMD64)] on win32
  Type "help", "copyright", "credits" or "license" for more information.
  >>> m = map(lambda x: x, [1, 2, 3])  # Just a dummy lambda function
  >>> m, type(m)
  ([1, 2, 3], <type 'list'>)
  >>> len(m)
  3
  

  
  

  Python 3.5.4 (v3.5.4:3f56838, Aug  8 2017, 02:17:05) [MSC v.1900 64 bit (AMD64)] on win32
  Type "help", "copyright", "credits" or "license" for more information.
  >>> m = map(lambda x: x, [1, 2, 3])
  >>> m, type(m)
  (<map object at 0x000001B4257342B0>, <class 'map'>)
  >>> len(m)
  Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
  TypeError: object of type 'map' has no len()
  >>> lm0 = list(m)  # Construct a list out of the generator
  >>> lm0, type(lm0)
  ([1, 2, 3], <class 'list'>)
  >>>
  >>> lm1 = list(m)  # Construct a list out of the same generator
  >>> lm1, type(lm1)  # Empty list this time - generator already consumed
  ([], <class 'list'>)
  

• The examples will be based on a directory called root_dir with the following structure (this example is for Win, but I have duplicated the folder tree for Ux(Lnx) as well):

  E:\Work\Dev\StackOverflow\q003207219>tree /f "root_dir"
  Folder PATH listing for volume Work
  Volume serial number is 00000029 3655:6FED
  E:\WORK\DEV\STACKOVERFLOW\Q003207219\ROOT_DIR
  │   file0
  │   file1
  │
  ├───dir0
  │   ├───dir00
  │   │   │   file000
  │   │   │
  │   │   └───dir000
  │   │           file0000
  │   │
  │   ├───dir01
  │   │       file010
  │   │       file011
  │   │
  │   └───dir02
  │       └───dir020
  │           └───dir0200
  ├───dir1
  │       file10
  │       file11
  │       file12
  │
  ├───dir2
  │   │   file20
  │   │
  │   └───dir20
  │           file200
  │
  └───dir3
  

Solutions

Programmatic approaches:

1. [Python]: os.listdir(path='.')

   Return a list containing the names of the entries in the directory given by path. The list is in arbitrary order, and does not include the special entries '.' and '..' ...

   
   

   >>> import os
   >>> root_dir = "root_dir"  # Path relative to current dir (os.getcwd())
   >>>
   >>> os.listdir(root_dir)  # List all the items in root_dir
   ['dir0', 'dir1', 'dir2', 'dir3', 'file0', 'file1']
   >>>
   >>> [item for item in os.listdir(root_dir) if os.path.isfile(os.path.join(root_dir, item))]  # Filter the items and only keep files (strip out directories)
   ['file0', 'file1']
   

   Here's a more elaborate example (code_os_listdir.py):

   import os
   from pprint import pformat
   
   
   def _get_dir_content(path, include_folders, recursive):
       entries = os.listdir(path)
       for entry in entries:
           entry_with_path = os.path.join(path, entry)
           if os.path.isdir(entry_with_path):
               if include_folders:
                   yield entry_with_path
               if recursive:
                   for sub_entry in _get_dir_content(entry_with_path, include_folders, recursive):
                       yield sub_entry
           else:
               yield entry_with_path
   
   
   def get_dir_content(path, include_folders=True, recursive=True, prepend_folder_name=True):
       path_len = len(path) + len(os.path.sep)
       for item in _get_dir_content(path, include_folders, recursive):
           yield item if prepend_folder_name else item[path_len:]
   
   
   def _get_dir_content_old(path, include_folders, recursive):
       entries = os.listdir(path)
       ret = list()
       for entry in entries:
           entry_with_path = os.path.join(path, entry)
           if os.path.isdir(entry_with_path):
               if include_folders:
                   ret.append(entry_with_path)
               if recursive:
                   ret.extend(_get_dir_content_old(entry_with_path, include_folders, recursive))
           else:
               ret.append(entry_with_path)
       return ret
   
   
   def get_dir_content_old(path, include_folders=True, recursive=True, prepend_folder_name=True):
       path_len = len(path) + len(os.path.sep)
       return [item if prepend_folder_name else item[path_len:] for item in _get_dir_content_old(path, include_folders, recursive)]
   
   
   def main():
       root_dir = "root_dir"
       ret0 = get_dir_content(root_dir, include_folders=True, recursive=True, prepend_folder_name=True)
       lret0 = list(ret0)
       print(ret0, len(lret0), pformat(lret0))
       ret1 = get_dir_content_old(root_dir, include_folders=False, recursive=True, prepend_folder_name=False)
       print(len(ret1), pformat(ret1))
   
   
   if __name__ == "__main__":
       main()
   

   Notes:

   • There are two implementations:
     • One that uses generators (of course in this example it seems useless, since I convert the result to a list immediately)
     • The classic one (function names ending in _old)
   • Recursion is used (to get into subdirectories)
   • For each implementations there are two functions:
     • One that starts with an underscore (_): "private" (should not be called directly) - that does all the work
     • The public one (wrapper over previous): it just strips off the initial path (if required) from the returned entries. It's an ugly implementation, but it's the only idea that I could come with at this point
   • In terms of performance, generators are generally a little bit faster (considering both creation and iteration times), but I didn't test them in recursive functions, and also I am iterating inside the function over inner generators - don't know how performance friendly is that
   • Play with the arguments to get different results

   
   

   Output:

   (py35x64_test) E:\Work\Dev\StackOverflow\q003207219>"e:\Work\Dev\VEnvs\py35x64_test\Scripts\python.exe" "code_os_listdir.py"
   <generator object get_dir_content at 0x000001BDDBB3DF10> 22 ['root_dir\\dir0',
    'root_dir\\dir0\\dir00',
    'root_dir\\dir0\\dir00\\dir000',
    'root_dir\\dir0\\dir00\\dir000\\file0000',
    'root_dir\\dir0\\dir00\\file000',
    'root_dir\\dir0\\dir01',
    'root_dir\\dir0\\dir01\\file010',
    'root_dir\\dir0\\dir01\\file011',
    'root_dir\\dir0\\dir02',
    'root_dir\\dir0\\dir02\\dir020',
    'root_dir\\dir0\\dir02\\dir020\\dir0200',
    'root_dir\\dir1',
    'root_dir\\dir1\\file10',
    'root_dir\\dir1\\file11',
    'root_dir\\dir1\\file12',
    'root_dir\\dir2',
    'root_dir\\dir2\\dir20',
    'root_dir\\dir2\\dir20\\file200',
    'root_dir\\dir2\\file20',
    'root_dir\\dir3',
    'root_dir\\file0',
    'root_dir\\file1']
   11 ['dir0\\dir00\\dir000\\file0000',
    'dir0\\dir00\\file000',
    'dir0\\dir01\\file010',
    'dir0\\dir01\\file011',
    'dir1\\file10',
    'dir1\\file11',
    'dir1\\file12',
    'dir2\\dir20\\file200',
    'dir2\\file20',
    'file0',
    'file1']
   

2. [Python]: os.scandir(path='.') (!!! Python 3.5+ !!! although I think that for earlier versions it was a separate module (also ported to Python 2))

   Return an iterator of os.DirEntry objects corresponding to the entries in the directory given by path. The entries are yielded in arbitrary order, and the special entries '.' and '..' are not included.

   Using scandir() instead of listdir() can significantly increase the performance of code that also needs file type or file attribute information, because os.DirEntry objects expose this information if the operating system provides it when scanning a directory. All os.DirEntry methods may perform a system call, but is_dir() and is_file() usually only require a system call for symbolic links; os.DirEntry.stat() always requires a system call on Unix but only requires one for symbolic links on Windows.

   
   

   >>> import os
   >>> root_dir = os.path.join(".", "root_dir")  # Explicitly prepending current directory
   >>> root_dir
   '.\\root_dir'
   >>>
   >>> scandir_iterator = os.scandir(root_dir)
   >>> scandir_iterator
   <nt.ScandirIterator object at 0x00000268CF4BC140>
   >>> [item.path for item in scandir_iterator]
   ['.\\root_dir\\dir0', '.\\root_dir\\dir1', '.\\root_dir\\dir2', '.\\root_dir\\dir3', '.\\root_dir\\file0', '.\\root_dir\\file1']
   >>>
   >>> [item.path for item in scandir_iterator]  # Will yield an empty list as it was consumed by previous iteration (automatically performed by the list comprehension)
   []
   >>>
   >>> scandir_iterator = os.scandir(root_dir)  # Reinitialize the generator
   >>> for item in scandir_iterator :
   ...     if os.path.isfile(item.path):
   ...             print(item.name)
   ...
   file0
   file1
   

   Notes:

   • It's similar to os.listdir
   • But it's also more flexible (and offers more functionality), more Pythonic (and in some cases, faster)

3. [Python]: os.walk(top, topdown=True, onerror=None, followlinks=False)

   Generate the file names in a directory tree by walking the tree either top-down or bottom-up. For each directory in the tree rooted at directory top (including top itself), it yields a 3-tuple (dirpath, dirnames, filenames).

   
   

   >>> import os
   >>> root_dir = os.path.join(os.getcwd(), "root_dir")  # Specify the full path
   >>> root_dir
   'E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir'
   >>>
   >>> walk_generator = os.walk(root_dir)
   >>> root_dir_entry = next(walk_generator)  # First entry corresponds to the root dir (that was passed as an argument)
   >>> root_dir_entry
   ('E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir', ['dir0', 'dir1', 'dir2', 'dir3'], ['file0', 'file1'])
   >>>
   >>> root_dir_entry[1] + root_dir_entry[2]  # Display the dirs and the files (that are direct descendants) in a single list
   ['dir0', 'dir1', 'dir2', 'dir3', 'file0', 'file1']
   >>>
   >>> [os.path.join(root_dir_entry[0], item) for item in root_dir_entry[1] + root_dir_entry[2]]  # Display all the entries in the previous list by their full path
   ['E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir0', 'E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir1', 'E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir2', 'E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir3', 'E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\file0', 'E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\file1']
   >>>
   >>> for entry in walk_generator:  # Display the rest of the elements (corresponding to every subdir)
   ...     print(entry)
   ...
   ('E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir0', ['dir00', 'dir01', 'dir02'], [])
   ('E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir0\\dir00', ['dir000'], ['file000'])
   ('E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir0\\dir00\\dir000', [], ['file0000'])
   ('E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir0\\dir01', [], ['file010', 'file011'])
   ('E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir0\\dir02', ['dir020'], [])
   ('E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir0\\dir02\\dir020', ['dir0200'], [])
   ('E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir0\\dir02\\dir020\\dir0200', [], [])
   ('E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir1', [], ['file10', 'file11', 'file12'])
   ('E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir2', ['dir20'], ['file20'])
   ('E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir2\\dir20', [], ['file200'])
   ('E:\\Work\\Dev\\StackOverflow\\q003207219\\root_dir\\dir3', [], [])
   

   Notes:

   • Under the scenes, it uses os.listdir (os.scandir where available)
   • It does the heavy lifting by recurring in subfolders

4. [Python]: glob.glob(pathname, *, recursive=False) ([Python]: glob.iglob(pathname, *, recursive=False))

   Return a possibly-empty list of path names that match pathname, which must be a string containing a path specification. pathname can be either absolute (like /usr/src/Python-1.5/Makefile) or relative (like ../../Tools/*/*.gif), and can contain shell-style wildcards. Broken symlinks are included in the results (as in the shell).
   ...
   Changed in version 3.5: Support for recursive globs using “**”.

   
   

   >>> import glob, os
   >>> wildcard_pattern = "*"
   >>> root_dir = os.path.join("root_dir", wildcard_pattern)  # Match every file/dir name
   >>> root_dir
   'root_dir\\*'
   >>>
   >>> glob_list = glob.glob(root_dir)
   >>> glob_list
   ['root_dir\\dir0', 'root_dir\\dir1', 'root_dir\\dir2', 'root_dir\\dir3', 'root_dir\\file0', 'root_dir\\file1']
   >>>
   >>> [item.replace("root_dir" + os.path.sep, "") for item in glob_list]  # Strip the dir name and the path separator from begining
   ['dir0', 'dir1', 'dir2', 'dir3', 'file0', 'file1']
   >>>
   >>> for entry in glob.iglob(root_dir + "*", recursive=True):
   ...     print(entry)
   ...
   root_dir\
   root_dir\dir0
   root_dir\dir0\dir00
   root_dir\dir0\dir00\dir000
   root_dir\dir0\dir00\dir000\file0000
   root_dir\dir0\dir00\file000
   root_dir\dir0\dir01
   root_dir\dir0\dir01\file010
   root_dir\dir0\dir01\file011
   root_dir\dir0\dir02
   root_dir\dir0\dir02\dir020
   root_dir\dir0\dir02\dir020\dir0200
   root_dir\dir1
   root_dir\dir1\file10
   root_dir\dir1\file11
   root_dir\dir1\file12
   root_dir\dir2
   root_dir\dir2\dir20
   root_dir\dir2\dir20\file200
   root_dir\dir2\file20
   root_dir\dir3
   root_dir\file0
   root_dir\file1
   

   Notes:

   • Uses os.listdir
   • For large trees (especially if recursive is on), iglob is preferred
   • Allows advanced filtering based on name (due to the wildcard)

5. [Python]: class pathlib.Path(*pathsegments) (!!! Python3+ !!! don't know if backported)

   >>> import pathlib
   >>> root_dir = "root_dir"
   >>> root_dir_instance = pathlib.Path(root_dir)
   >>> root_dir_instance
   WindowsPath('root_dir')
   >>> root_dir_instance.name
   'root_dir'
   >>> root_dir_instance.is_dir()
   True
   >>>
   >>> [item.name for item in root_dir_instance.glob("*")]  # Wildcard searching for all direct descendants
   ['dir0', 'dir1', 'dir2', 'dir3', 'file0', 'file1']
   >>>
   >>> [os.path.join(item.parent.name, item.name) for item in root_dir_instance.glob("*") if not item.is_dir()]  # Display paths (including parent) for files only
   ['root_dir\\file0', 'root_dir\\file1']
   

   Notes:

   • This is one way of achieving our goal
   • It's the OOP style of handling paths
   • Offers lots of functionalities

6. [Python]: dircache.listdir(path) (!!! removed in Python3 !!!)

   • But, according to ${PYTHON_SRC_DIR}/Lib/dircache.py: ~#20+ (from v2.7.14), it's just a (thin) wrapper over os.listdir

   
   

   def listdir(path):
       """List directory contents, using cache."""
       try:
           cached_mtime, list = cache[path]
           del cache[path]
       except KeyError:
           cached_mtime, list = -1, []
       mtime = os.stat(path).st_mtime
       if mtime != cached_mtime:
           list = os.listdir(path)
           list.sort()
       cache[path] = mtime, list
       return list
   

7. [man]: OPENDIR(3) / [man]: READDIR(3) / [man]: CLOSEDIR(3) via [Python]: ctypes — A foreign function library for Python (!!! Ux specific !!!)

   ctypes is a foreign function library for Python. It provides C compatible data types, and allows calling functions in DLLs or shared libraries. It can be used to wrap these libraries in pure Python.

   code_ctypes.py:

   #!/usr/bin/env python3
   
   import sys
   from ctypes import Structure, \
       c_ulonglong, c_longlong, c_ushort, c_ubyte, c_char, c_int, \
       CDLL, POINTER, \
       create_string_buffer, get_errno, set_errno, cast, sizeof
   
   
   DT_DIR = 4
   DT_REG = 8
   
   char256 = c_char * 256
   
   class LinuxDirent64(Structure):
       _fields_ = [
           ("d_ino", c_ulonglong),
           ("d_off", c_longlong),
           ("d_reclen", c_ushort),
           ("d_type", c_ubyte),
           ("d_name", char256),
       ]
   
   LinuxDirent64Ptr = POINTER(LinuxDirent64)
   
   libc_dll = CDLL(None)
   opendir = libc_dll.opendir
   readdir = libc_dll.readdir
   closedir = libc_dll.closedir
   libc_dll.__errno_location.restype = POINTER(c_int)
   errno_loc_func = libc_dll.__errno_location
   
   
   def _get_errno():
       return "errno: {:d}({:d})".format(get_errno(), errno_loc_func().contents.value)
   
   
   def get_dir_content(path):
       ret = [path, list(), list()]
       dir_stream = opendir(create_string_buffer(path.encode()))
       if (dir_stream == 0):
           print("opendir returned NULL ({:s})".format(_get_errno()))
           return ret
       set_errno(0)
       dirent_addr = readdir(dir_stream)
       while dirent_addr:
           dirent_ptr = cast(dirent_addr, LinuxDirent64Ptr)
           dirent = dirent_ptr.contents
           name = dirent.d_name.decode()
           if dirent.d_type & DT_DIR:
               if name not in (".", ".."):
                   ret[1].append(name)
           elif dirent.d_type & DT_REG:
               ret[2].append(name)
           dirent_addr = readdir(dir_stream)
       if get_errno() or errno_loc_func().contents.value:
           print("readdir returned NULL ({:s})".format(_get_errno()))
       closedir(dir_stream)
       return ret
   
   
   def main():
       print("{:s} on {:s}\n".format(sys.version, sys.platform))
       root_dir = "root_dir"
       entries = get_dir_content(root_dir)
       print(entries)
   
   
   if __name__ == "__main__":
       main()
   

   Notes:

   • It loads the three functions from libc (loaded in the current process) and calls them (for more details check [Stack Overflow]: How do I check whether a file exists using Python? (@CristiFati's answer) - last notes from item #4.). That would place this approach very close to the Python / C edge
   • LinuxDirent64 is the ctypes representation of struct dirent64 from dirent.h (so are the DT_* constants) from my machine: Ubtu 16 x64 (4.10.0-40-generic and libc6-dev:amd64). On other flavors/versions, the struct definition might differ, and if so, the ctypes alias should be updated, otherwise it will yield Undefined Behavior
   • errno_loc_func (and everything related to it) is because the funcs set errno in case of error, and I need to check its value. Apparently, get_errno doesn't work (with an invalid name, opendir returns NULL, but get_errno still returns 0), or I didn't figure it out yet
   • It returns data in the os.walk's format. I didn't bother to make it recursive, but starting from the existing code, that would be a fairly trivial task
   • Everything is doable on Win as well, the data (libraries, functions, structs, constants, ...) differ

   
   

   Output:

   cfati@testserver:~/work/stackoverflow/q003207219$ ./code_ctypes.py
   3.5.2 (default, Nov 23 2017, 16:37:01)
   [GCC 5.4.0 20160609] on linux
   
   ['root_dir', ['dir3', 'dir2', 'dir0', 'dir1'], ['file0', 'file1']]
   

8. [ActiveState]: win32file.FindFilesW (!!! Win specific !!!)

   Retrieves a list of matching filenames, using the Windows Unicode API. An interface to the API FindFirstFileW/FindNextFileW/Find close functions.

   
   

   >>> import os, win32file, win32con
   >>> root_dir = "root_dir"
   >>> wildcard = "*"
   >>> root_dir_wildcard = os.path.join(root_dir, wildcard)
   >>> entry_list = win32file.FindFilesW(root_dir_wildcard)
   >>> len(entry_list)  # Don't display the whole content as it's too long
   8
   >>> [entry[-2] for entry in entry_list]  # Only display the entry names
   ['.', '..', 'dir0', 'dir1', 'dir2', 'dir3', 'file0', 'file1']
   >>>
   >>> [entry[-2] for entry in entry_list if entry[0] & win32con.FILE_ATTRIBUTE_DIRECTORY and entry[-2] not in (".", "..")]  # Filter entries and only display dir names (except self and parent)
   ['dir0', 'dir1', 'dir2', 'dir3']
   >>>
   >>> [os.path.join(root_dir, entry[-2]) for entry in entry_list if entry[0] & (win32con.FILE_ATTRIBUTE_NORMAL | win32con.FILE_ATTRIBUTE_ARCHIVE)]  # Only display file "full" names
   ['root_dir\\file0', 'root_dir\\file1']
   

   Notes:

   • win32file.FindFilesW is part of [GitHub]: Python for Windows (pywin32) Extensions, which is a Python wrapper over WINAPIs
   • The documentation link is from https://www.activestate.com, as I didn't find any pywin32 official documentation

9. Install some (other) third-party package that does the trick
   • Most likely, will rely on one (or more) of the above (maybe with slight customizations)

Notes (about the stuff above):

• Code is meant to be portable (except places that target a specific area - which are marked) or cross:
  • platform (Ux, Win, )
  • Python version (2, 3, )
• Multiple path styles (absolute, relatives) were used across the above variants, to illustrate the fact that the "tools" used are flexible in this direction
• os.listdir and os.scandir use opendir / readdir / closedir ([MSDN]: FindFirstFile function / [MSDN]: FindNextFile function / [MSDN]: FindClose function) (via "${PYTHON_SRC_DIR}/Modules/posixmodule.c")
• win32file.FindFilesW uses those (Win specific) functions as well (via "${PYWIN32_SRC_DIR}/win32/src/win32file.i")
• get_dir_content (from point #1.) can be implemented using any of these approaches (some will require more work and some less)
  • Some advanced filtering (instead of just file vs. dir) could be done: e.g. the include_folders argument could be replaced by another one (e.g. filter_func) which would be a function that takes a path as an argument: filter_func=lambda x: True (this doesn't strip out anything) and inside get_dir_content something like: if not filter_func(entry_with_path): continue (if the function fails for one entry, it will be skipped), but the more complex the code becomes, the longer it will take to execute
• Nota bene! Since recursion is used, I must mention that I did some tests on my laptop (Win 10 x64), totally unrelated to this problem, and when the recursion level was reaching values somewhere in the (990 .. 1000) range (recursionlimit - 1000 (default)), I got StackOverflow :). If the directory tree exceeds that limit (I am not an FS expert, so I don't know if that is even possible), that could be a problem.
  I must also mention that I didn't try to increase recursionlimit because I have no experience in the area (how much can I increase it before having to also increase the stack at OS level), but in theory there will always be the possibility for failure, if the dir depth is larger than the highest possible recursionlimit (on that machine)
• The code samples are for demonstrative purposes only. That means that I didn't take into account error handling (I don't think there's any try / except / else / finally block), so the code is not robust (the reason is: to keep it as simple and short as possible). For production, error handling should be added as well

End of Part One ¹

_{1. Due to the fact that SO's post (question / answer) limit is 30000 chars ([SE.Meta]: Knowing Your Limits: What is the maximum length of a question title, post, image and links used?), the answer was split in 2 parts. Please also visit [SO]: How do I list all files of a directory? (@CristiFati's answer - "Part Two").}

Part Two ¹

Solutions (continued)

Other approaches:

1. Use Python only as a wrapper

   • Everything is done using another technology
   • That technology is invoked from Python

   • The most famous flavor that I know is what I call the system administrator approach:

     • Use Python (or any programming language for that matter) in order to execute shell commands (and parse their outputs - in general this approach is to be avoided, since if some command output format slightly differs between OS versions/flavors, the parsing code should be adapted as well; not to mention non EN locales)
     • Some consider this a neat hack
     • I consider it more like a lame workaround (gainarie), as the action per se is performed from shell (cmd in this case), and thus doesn't have anything to do with Python.
     • Filtering (grep / findstr) or output formatting could be done on both sides, but I'm not going to insist on it. Also, I deliberately used os.system instead of subprocess.Popen.

     (py35x64_test) E:\Work\Dev\StackOverflow\q003207219>"e:\Work\Dev\VEnvs\py35x64_test\Scripts\python.exe" -c "import os;os.system(\"dir /b root_dir\")"
     dir0
     dir1
     dir2
     dir3
     file0
     file1
     

End of Part Two ¹

_{1. Due to the fact that SO's post (question / answer) limit is 30000 chars ([SE.Meta]: Knowing Your Limits: What is the maximum length of a question title, post, image and links used?), the answer was split in 2 parts. Please make sure to read [SO]: How do I list all files of a directory? (@CristiFati's answer - "Part One") before.}

Execute findfiles() with a directory as a parameter and it will return a list of all files in it.

import os
def findfiles(directory):
    objects = os.listdir(directory)  # find all objects in a dir

    files = []
    for i in objects:  # check if very object in the folder ...
        if os.path.isfile(os.path.join(directory, i)):  # ... is a file.
            files.append(i)  # if yes, append it.
    return files

Another very readable variant for Python 3.4+ is using pathlib.Path.glob:

from pathlib import Path
folder = '/foo'
[f for f in Path(folder).glob('*') if f.is_file()]

It is simple to make more specific, e.g. only look for Python source files which are not symbolic links, also in all subdirectories:

[f for f in Path(folder).glob('**/*.py') if not f.is_symlink()]

Really simple version:

import os
[f for f in os.listdir(os.getcwd) if ...]

import os
import os.path


def get_files(target_dir):
    item_list = os.listdir(target_dir)

    file_list = list()
    for item in item_list:
        item_dir = os.path.join(target_dir,item)
        if os.path.isdir(item_dir):
            file_list += get_files(item_dir)
        else:
            file_list.append(item_dir)
    return file_list

Here I use a recursive structure.