How to Use This Book

Although it can be read sequentially, the book was written for "random access." You'll probably pick it up when you seek a solution to a problem. Each chapter groups projects that cover similar tasks, so start with the table of contents, and choose the chapter that seems closest to your task. Scan the list of projects in the chapter, and choose the project that looks like the closest fit. Then read the introduction to confirm that the project is the right one; each project introduction starts with a typical question that the project will answer and then outlines the material it covers.

Learn More

Project 22 shows you how to view binary and compressed files.

Follow the project through, preferably in front of a computer with a Terminal window open so you can try the examples. Projects are written to be self-contained, and except for Chapter 1, most assume some basic knowledge and competence at the command line. If you are new to Unix (or a bit rusty), Chapter 1 is essential reading.

Note

When creating the patch file, be sure that the filenames passed to diff are in the correct order (name of outdated file, followed by up-to-date version); otherwise, the patch will be applied in reverse.

Each project covers just the commands required to complete the task at hand. It may draw on many technologies and techniques, distilling the necessary information for you. It won't give an encyclopedic description of a command or list all its available options. If you want to know more about one of the commands used to complete a task, reach for the Unix manual pages. Pointers directing you to do so appear throughout the book, and the manual is also the focus of Project 3.

Sometimes you want to discover more or have further interest in one of the technologies a project uses. You might want to extend one of the examples. Projects acknowledge this by giving you many links to other projects that discuss a technique or command in detail or that use it in another way. Think of the Learn More links as being like HTML hyperlinks to other projects in the book. You'll see them in the margins, like the example to the left.

Directories and Files

In Unix, the term directory is used instead of folder. Folder comes from the desktop analogy and the visual representation of directories. The term file is often used in a general sense to mean both files and directories. Technically, in Unix, a directory is just a file.

The margins also use Notes to give additional and important information, caveats, or problems you might encounter.

Sidebars give additional but nonessential explanatory information.

Finally, the margins are littered with great tips like the one to the left.

Tip

To find out which signals a command or daemon respects, check its man page, and search for the section "SIGNALS."

Sometimes you'll see a warning where you might encounter problems or potentially do something damaging.

Warning

This is an example warning. A warning is always in the main body of text and introduced by the warning graphic you see above. Always take care to read and understand warnings.

Project 100 lists a very large number of Unix commands, each with a brief description of its purpose. The commands are organized into categories and grouped together by similar functionality. Where a command is covered by a project in this book, the project number is shown in brackets.

The appendix lists the Unix terminology, techniques, and concepts covered in the book. Each term is cross-referenced to the projects(s) that cover it.