Chapter 35. Command-line Masterclass

Raymond, Eric. The Art of Unix Programming. Addison-Wesley, 2004.

IN THIS CHAPTER

• Why Use the Shell?

• Basic Commands

• Combining Commands Together

• Multiple Terminals

• Reference

In the earlier years of Linux, people made a big fuss of the graphical environments that were available they rushed to tell new users that you really did not need to keep going back to the command line to type things. Now Linux is more mature, people accept that the command line is still a reality, and a welcome one. While the GUI does indeed make life easier for day-to-day tasks, your options are limited by what the developers wanted you to have you cannot bring commands together in new ways, and neither can you use any of the GUI features if, for example, your GUI is broken. It does happen!

In his book The Art of Unix Programming*, Eric Raymond wrote a short story that perfectly illustrates the power of the command line versus the GUI. It's reprinted here with permission, for your reading pleasure:

One evening, Master Foo and Nubi attended a gathering of programmers who had met to learn from each other. One of the programmers asked Nubi to what school he and his master belonged. Upon being told they were followers of the Great Way of Unix, the programmer grew scornful.

"The command-line tools of Unix are crude and backward," he scoffed. "Modern, properly designed operating systems do everything through a graphical user interface."

Master Foo said nothing, but pointed at the moon. A nearby dog began to bark at the master's hand.

"I don't understand you!" said the programmer.

Master Foo remained silent, and pointed at an image of the Buddha. Then he pointed at a window.

"What are you trying to tell me?" asked the programmer.

Master Foo pointed at the programmer's head. Then he pointed at a rock.

"Why can't you make yourself clear?" demanded the programmer.

Master Foo frowned thoughtfully, tapped the programmer twice on the nose, and dropped him in a nearby trash can.

As the programmer was attempting to extricate himself from the garbage, the dog wandered over and piddled on him.

At that moment, the programmer achieved enlightenment.

Whimsical as the story is, it does illustrate that there are some things that the GUI just does not do well. Enter the command line: It is a powerful and flexible operating environment on Linux, and if you practice can actually be quite fun, too!

In this chapter, you will learn how to master the command line so that you are able to perform common tasks through it, and also link commands together to create new command groups. We will also be looking at the two most popular Linux text editors: Vim and Emacs. The command line is also known as the shell, the console, the command prompt, and the CLI (command-line interpreter). For the purposes of this chapter these are interchangeable, although there are fine-grained differences between them!