“Getting Around,” the first part of this book, starts off with a primer on Darwin, the Unix foundation of Mac OS X. Chapter 1 is packed with useful tricks on using the terminal, ranging from scripting to customizing the tcsh environment that is installed as the default. The obligatory Emacs and vi keyboard command guides (though no ASCII table) are included, along with a list of just about every command, from apropos to zcat, categorized by function. A brief second chapter provides information on customizing the boot process, ranging from adding startup items and cron jobs to customizing the login window. Chapter 3, perhaps the most important chapter in the book for experienced administrators, presents an extremely thorough and thoughtful description of Mac OS X’s directory service architecture, Open Directory. User and group management is explained, both from a graphical user interface (GUI) tool perspective, and from the scriptable command line.

“Building Applications,” the second part of the book, is devoted to the compilers, libraries, headers, and frameworks that ship with Apple’s excellent developer tools. Chapter 4 skims through the developer tools and the languages that can be compiled out of the box. Some architectural issues, mostly for writing portable code, are briefly outlined. The fifth chapter covers the libraries, headers, and frameworks, but it is too brief to really be considered a primer on programming for the OS; it seems more intended to help someone who will be compiling downloaded software, which is what the next chapter covers with its discussion of fink, a popular command-line tool that is similar to apt-get. A good discussion on the package formats used by Mac OS X is provided, along with information about how to create one’s own packages and disk images using PackageMaker and Disk Copy, respectively, along with command-line utilities.

The third part of the book, “Beyond the User Space,” is the part that meets the demands of true “Unix geeks.” Chapter 7 explains how to get the Darwin source through concurrent versions system (CVS), and how to build and install the new kernel, something that most administrators will probably not end up doing. Chapter 8 discusses common system management tools, mostly Unix standards like top and sysctl, but also Apple-specific tools like nvram, which is used to manage Open Firmware variables. The last chapter, which covers the X Windows system and building X11 applications, is useful, though already outdated by Apple’s release of an easily installable X11 server. The discussion on connecting to other X11 systems and VNC, however, is quite useful.

The book ends with similarly useful appendixes on the Mac OS X filesystem layout (where important differences from other versions of Unix are omnipresent), and on “the missing manpages” for many of the command-line utilities in Mac OS X. Interestingly, the appendixes seem to represent th e part of the book that will most likely be most often used by system administrators.

The benefit of the book not being overly “geeky” is that it serves the dual purpose of teaching Macintosh users Unix, and Unix users Macintosh. The book, which purports to be Mac OS X for Unix geeks, might benefit by having the subtitle aka Unix for Macintosh geeks. It is an excellent follow-up to Learning Unix for Mac OS X [1] for the power user, and it also covers the gaps that need to be addressed to make an expert Unix administrator’s skills applicable to Mac OS X.