Iterating Over Files in a Directory with Python

Python provides several ways to iterate over files in a directory. In this tutorial, we will explore different methods to achieve this task efficiently.

Introduction to os Module

The os module is a built-in Python module that provides a way of using operating system dependent functionality. To iterate over files in a directory using the os module, you can use the listdir() function, which returns a list containing the names of the entries in the directory given by the path.

import os

for filename in os.listdir("/path/to/dir/"):
    if filename.endswith(".asm"):
        print(os.path.join("/path/to/dir/", filename))

Introduction to pathlib Module

The pathlib module is another built-in Python module that provides an object-oriented way of interacting with the file system. To iterate over files in a directory using the pathlib module, you can use the glob() or rglob() function.

from pathlib import Path

for path in Path("/path/to/dir/").glob("*.asm"):
    print(path)

To recursively search for files in subdirectories, you can use the rglob() function:

from pathlib import Path

for path in Path("/path/to/dir/").rglob("*.asm"):
    print(path)

Introduction to glob Module

The glob module is a built-in Python module that provides a way of finding files matching certain patterns. To iterate over files in a directory using the glob module, you can use the iglob() function.

import glob

for filepath in glob.iglob("/path/to/dir/*.asm"):
    print(filepath)

To recursively search for files in subdirectories, you can pass the recursive=True argument to the glob() function:

import glob

for filepath in glob.glob("/path/to/dir/**/*.asm", recursive=True):
    print(filepath)

Introduction to os.scandir() Function

The os.scandir() function is a more efficient way of iterating over files in a directory, especially when you need additional file information. This function returns an iterator that yields DirEntry objects, which contain information about the file.

import os

with os.scandir("/path/to/dir/") as it:
    for entry in it:
        if entry.name.endswith(".asm") and entry.is_file():
            print(entry.name, entry.path)

Choosing the Right Method

The choice of method depends on your specific use case. If you need to recursively search for files in subdirectories, consider using the pathlib or glob module. If you need additional file information, consider using the os.scandir() function.

In summary, Python provides several ways to iterate over files in a directory, each with its own strengths and weaknesses. By choosing the right method for your use case, you can efficiently achieve this task.