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reddalo • today at 8:46 AM • 1 reply • view on HN

Modern macOS still lets you keep editing a file even if it's moved somewhere else, I think because file editing is done with the actual file ID rather than its bare location on the filesystem.

Windows, on other hand, prevents you from doing this in my experience.

Replies

ctippett • today at 11:10 AM

Correct. It's not so much "modern macOS" though, it's a feature of APFS[1].

  > Most of us still think of file systems in simple terms, like HFS+. Duplicate or copy a file, and macOS copies all the data to a new storage area and makes that a different file. Thankfully, APFS is much smarter than that, and regularly – indeed, as a rule whenever it can – doesn’t copy any data at all. What it does is create a clone file, which is a bit like a hard link, in that the file record points to the same data as the original. Unlike a hard link, the clone is a separate file, with its own iNode.
[1] https://eclecticlight.co/2021/05/29/explainer-deduplication/