Create space-saving clones on macOS with Python

Create space-saving clones on macOS with Python

The standard Mac filesystem, APFS , has a feature called space-saving clones. This allows you to create multiple copies of a file without using additional disk space – the filesystem only stores a single copy of the data.

Although cloned files share data, they’re independent – you can edit one copy without affecting the other (unlike symlinks or hard links). APFS uses a technique called copy-on-write to store the data efficiently on disk – the cloned files continue to share any pieces they have in common.

Cloning files is both faster and uses less disk space than copying. If you’re working with large files – like photos, videos, or datasets – space-saving clones can be a big win.

Several filesystems support cloning, but in this post, I’m focusing on macOS and APFS.

For a recent project, I wanted to clone files using Python. There’s an open ticket to support file cloning in the Python standard library. In Python 3.14, there’s a new Path.copy() function which adds support for cloning on Linux – but there’s nothing yet for macOS.

In this post, I’ll show you two ways to clone files in APFS using Python.

What are the benefits of cloning?

There are two main benefits to using clones rather than copies.

Cloning files uses less disk space than copying

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