If generating QuickLook thumbnails and previews, and indexing metadata for Spotlight, depend on UTIs, how come they tolerate misleading file extensions? A simple practical demo.
metadata
Soon after introducing iCloud and iCloud Drive, Apple changed the way most metadata was handled to ensure it was synced up to the cloud. Recently this has been reversed, and little metadata is now synced. Was this an accident or intentional? What is the workaround?
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.
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.
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.
When Spotlight can’t find the files you expect it to, it could be that they weren’t indexed, or that Spotlight’s search has failed to find their index entries. Here’s how to tell those apart and work out what went wrong.
The Eclectic Light Company 