For the Unix administrator
by Tim Orbaker
Mac OS X. It's not perfect, but it's light years ahead of where it has been. Unix administrators who have in the past "been stuck" with Mac users should be happy to hear this one: Apple's new OS is now Unix. Mac users need not panic, however. The new Aqua window manager (user interface) can handle anything Mac users could want to do without ever exposing them to a command prompt. What's more, the OS's integration of "Classic" Mac applications is almost completely transparent -- all while sporting the full power of Unix under the hood.
How It Works
Mac OS X runs on Darwin. Derived from the Mach and FreeBSD kernels, Darwin is a fully POSIX compliant Unix kernel. All the expected utilities are there except development tools. But a quick visit to macaddict.com turned up a script that installed the development tools from the Darwin package in no time flat. It's an unsupported hack, but it does work relatively well. Most of my test code compiled and ran without errors or modification. On the bright side, Apple plans to make development tools available for download in mid October (see http://developer.apple.com/membership/macosx.html)
The file system hierarchy is similar to what you might expect on a standard Unix distribution with several additional directories. File permission and ownership management, while routine to Unix administrators, will be a huge shock to the system for veteran Mac users, as all unowned files (read: everything that you now own) are owned by root at startup.
For Unix administrators, there's one special issue to note. With Apple's HFS+ (Hierarchical File System) , file name case is preserved but not significant. If you chose to use the UFS (Unix File System) file system, case is significant, but you must reformat your drive during installation. If you want to partition your file system during installation, you're out of luck. There is no support for drive partitioning at install time. This is a serious oversight on Apple's part.
As with other Unix OSes, when you install OS X, you must create a user for the local machine. However, users don't appear to be kept in the standard /etc/passwd file, and you must use the GUI to manage them as there doesn't appear to be a useradd command. Also group management is all but non-existent. Some improvements in this area would be welcome.
Apple's OS X definitely still a beta, both shining with promise and smudged by the inevitable bugs. All the expected Unix services and tools are included except compilers. Once the rough edges smooth out, however, I can't imagine Unix administrators that would object to Mac OS X on their network. They'll find themselves right at home once they open a terminal window.