This isn't a book for beginners, but depending on what you are looking for it isn't totally advanced reading. Part I (Getting Around) is an assortment of 10 chapters - Inside the Terminal, Searching and Metadata, Startup, etc. - that are really just deeper dives. Once you have gotten past the "where's the terminal?" stage they provide good, useful information for any user who expects to spend time on the command line. Or who simply wants to know how things work.
But with Part II (Building Applications) the dive becomes much deeper, focusing on compiler requirements, libraries, frameworks, dynamic linking, and all the other minutia that a serious developer needs, especially one making the transition from the Unix world. If you are completely Mac based and are happy with Xcode you may find this is overkill. Later sections deal with Working with Packages, Serving and System Management, and some miscellaneous points.
Rothman and Jepson's writing style is a bit dry, and in the deeper sections they will often make assumptions about how well versed you are in Unix. Even in the Unix world there aren't a lot of people who are linking and loading experts and a little more effort at explaining the terms would have been appreciated. Come to think of it that's a standards fault anywhere in the Unix world - people keep assuming that the reason you are reading a book is that you already know what's in it - so I shouldn't complain.
Still, this is a good reference book. If I ever do want to create packages from the command line this will be my first stop. It belongs on the shelves of all Mac professionals, geeks or not.
