Traces the path of metadata from inside a PDF document and its extended attributes, to those in Spotlight’s indexes and displayed in the Finder. Only a third survived that journey.
extended attributes
What happens when you move a file with metadata attached in extended attributes to iCloud Drive? Which of those are preserved when you access that file from another Mac?
Two significant indexing errors when processing RTF and image files caused search failures. Display in the Finder is also insufficient to make these xattrs as useful as they could be.
How to select the most appropriate way of storing metadata, limitations of Finder Comments and Tags, which extended attributes are best, and which utilities to edit and manage them.
A simple and accessible way of categorising folders, they’re stored as extended attributes, and robust. They work best with up to 7 categories, but can confuse with many different text labels.
Although easy to add to documents, Finder comments work strangely, and can prove fragile. They can also be used to conceal malicious code by steganography, but there are better options.
Introduced in Mac OS X 10.4 to extend resource forks, they have flourished since. Explains their storage, how they persist or don’t, with an appendix explaining their flags.
Introduced in Catalina to enable ‘privacy by user intent’, these contain header-UUID pairs, with the UUID identifying the app granted access. But UUIDs change with every restart, so can’t be used to track access prior to the current session.
A complex set of rules with optional flags determines whether any given xattr is preserved when copying, saving, syncing with a cloud service, backing up, and more. Here they are.
Information about the data in a file can be found in different places: in the file’s attributes, in extended attributes that tend to be Mac-only, and embedded with the data, as in EXIF.
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