Find a File in Python

Finding files in Python can be a challenge when the file's location varies across different systems. Luckily, Python provides the os.walk module that enables you to traverse directories and locate files effortlessly.

os.walk for File Searching

os.walk creates a generator object that iterates over a directory and its subdirectories, yielding three tuples for each iteration:

• root (str): Absolute path to the current directory
• dirs (list): List of subdirectories within the current directory
• files (list): List of files within the current directory

Finding a Single File

To find the first occurrence of a specific file, simply iterate over the yielded tuples and check if the file name is in the list of files:

import os

def find(name, path):
    for root, dirs, files in os.walk(path):
        if name in files:
            return os.path.join(root, name)

Finding All Occurrences of a File

To find all occurrences of a file, create a list to store the matches:

def find_all(name, path):
    result = []
    for root, dirs, files in os.walk(path):
        if name in files:
            result.append(os.path.join(root, name))
    return result

Matching File Patterns

To search for files that match a pattern, use the fnmatch module:

import os, fnmatch
def find(pattern, path):
    result = []
    for root, dirs, files in os.walk(path):
        for name in files:
            if fnmatch.fnmatch(name, pattern):
                result.append(os.path.join(root, name))
    return result

find('*.txt', '/path/to/dir')