Macintosh Terminal Pocket Guide

What’s in This Book?

This book is a short guide to the Terminal, not a comprehensive reference. We cover important, useful aspects of the Terminal (and its partner, the “shell”) so you can work productively. We do not, however, present every single command and every last option (our apologies if your favorite was omitted), nor delve into detail about OS X internals. Short, sweet, and essential, that’s our motto.

We focus on commands, the words typed on a command line to tell your Macintosh what to do. Here’s an example command that counts lines of text in a file, myfile:

wc -l myfile

We’ll cover the most important commands for the average user, such as ls (list files), grep (search for text in a file), kill (terminate programs), and df (measure free disk space), plus some advanced commands like dscl (manage users and groups) and launchctl (run services and scheduled jobs). We assume you are already familiar with the Mac desktop and the Finder.

We’ve organized the material by function to provide a concise learning path. For example, to help you view the contents of a file, we introduce all file-viewing commands together: cat for short text files, less for longer ones, od for binary files, and so on. Then we explain each command in turn, briefly presenting its common uses and options.

At press time, the current version of OS X is Lion (10.7).