Taylor - Learning Unix for OS X

by Dave Taylor

Copyright 2016 Dave Taylor. All rights reserved.

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978-1-491-93998-7

[LSI]

Fifteen years ago, when Apple jumped from Mac OS 9 to Mac OS X (pronounce that oh-ess ten to sound cool), the entire experience of using a Mac system changed dramatically. Heck, many of you reading this have never known a nonOS X Mac interface! There were a lot of interface changes, but the biggest update when Apple switched operating systems was that every machine gained multitasking and multiuser capabilities.

Beneath the shiny graphical interface of OS X lies an operating system called Unix (pronounced you-nicks): specifically, UC Berkeleys BSD Unix and the Mach kernel, a multiuser, multitasking operating system. Being multiuser means OS X allows multiple users to share the same system, each with their own settings, preferences, and separate areas in the filesystem, secured from other users prying eyes. Being multitasking means OS X can easily run many different applications at the same time, and if one of those applications crashes or hangs, the entire system doesnt need to be rebooted. Instead, you just force quit the application thats causing the Spinning Beach Ball of Death (you know, when the mouse pointer turns into a spinning color wheel that just wont stop rotating) and either relaunch it or proceed with your work in other apps.

Other than the aforementioned advantages, the fact that OS X has Unix under the hood doesnt matter to users who simply want to use its slick graphical interface to run their applications or manage their files. But it opens up a world of possibilities for users who want to dig a little deeper. The Unix command-line interface, which is accessible through the Terminal application (you can find this app in /Applications/Utilities), provides an enormous amount of power for intermediate and advanced users. Whats more, once youve learned to use Unix in OS X, youll also be able to use the command line in other versions of Unix, such as FreeBSD (from which OS X derives its Unix core) or even the hugely popular Linux.

This book is designed to teach Mac users the basics of Unix. Youll learn how to use the command line (which Unix users refer to as the shell) and the filesystem, as well as some of Unixs most useful commands. Ill also give you a tour of some useful Unix commands that Apples team has written and are included with every Mac systemutilities that let you really gain control over your system.

Unix is a complex and powerful system, so I can only scratch the surface, but Ill also tell you how to deepen your Unix knowledge once youre ready for more.