Finder information
From Just Solve the File Format Problem
Finder information is a set of data structures containing Macintosh-specific metadata about a file or folder, including the presentation of its icon.
Formats that can include such information include HFS, AppleDouble, MacBinary, and ZIP (in some Mac-specific extra fields).
Certain details about the data structures have evolved over the years, so any given source of information about them might be incomplete.
Format details
Information about a file is contained in two 16-bytes structures, named FInfo and FXInfo. Information about a folder is contained in two 16-bytes structures, named DInfo and DXInfo.
The first 8 bytes of FInfo contain the Macintosh type/creator codes.
Specifications
- Inside Macintosh - Macintosh Toolbox Essentials → "Finder Interface Reference" section starting on p. 7-46
- An HTML version (from archive.org)
- In some SDKs, the structures are defined in a file named Finder.h (example: [1])