HFSDebug 4.0 and New HFS+ Features
Amit Singh (via John Siracusa):
The most interesting technical things about HFS+ are not its features, but how several of the newer features are implemented. With the goal of retaining backward compatibility, new features have often been retrofitted, or shoehorned, if you will, into HFS+. Knowing such implementation details invokes different reactions in different people, ranging from “That’s a nifty way to implement this!” to “Gross!” This is something you can decide for yourself with the help of HFSDebug, which can show you exactly how the file system works.