Traversing folders

When working with a path in the filesystem, it's common the need to find all files contained directly or in subfolders. Think about copying a directory or computing its size; in both cases, you will need to fetch the complete list of files included in the directory you want to copy, or for which you want to compute the size.

How to do it...

The steps for this recipe are as follows:

1. The os.walk function in the os module is meant to traverse a directory recursively, its usage is not immediate, but with little effort, we can wrap it into a convenient generator of all the contained files:

import os

def traverse(path):
    for basepath, directories, files in os.walk(path):
        for f in files:
            yield os.path.join(basepath, f)

2. Then, we can just iterate over traverse and apply whatever operation we need on top of it:

for f in traverse('.'):
    print(f)

How it works...

The os.walk function navigates the directory and all its subfolders. For each directory that it finds...