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A Novel Concept in Editing: emacs Makes Sense

We don’t want to get your hopes up, but emacs is much easier to use than vi . The reason is that it doesn’t have the mysterious modes that require you to remember at every moment whether the program is expecting a command or text.
On the other hand, commands in emacs aren’t exactly intuitive. Still, we like them better. In case you are wondering, the name emacs comes from editor macros because the original version of emacs was written as an extension to an early text editor called teco , an editor that makes ed (see the section "Talk to Mr.

ed ," at the end of this chapter) look like the winner of the Nobel prize for user-friendliness. (Scary thought, isn’t it?) To run emacs , type this line:

emacs eating.peas

You replace eating.peas with the name of the file you want, of course. If the file you name doesn’t exist, emacs creates it. Like vi , emacs displays a full-screen view of your file, as shown in Figure 10-2. On the bottom line of the screen is the status line, which tells you the name of the file you are editing and other, less interesting information.

Figure 10-2: The GNU Emacs display in a text console. At the bottom of the screen, emacs displays in the status line the filename and other mysterious information.

A tale of two emacs

Unlike vi , emacs does not automatically come with UNIX. Because most versions of emacs are distributed for free, however, most systems have it or can get it. By far the two most common versions of emacs are GNU Emacs and XEmacs. Despite the name, XEmacs runs under both X Windows and text-based consoles, and so does GNU Emacs. The basic commands are the same for both versions, and the most obvious differences between the two are the button bars and more sophisticated 3-D look to the windows in XEmacs. (Compare the difference in Figures 10-3 and 10-4.) Other than that, it really doesn’t matter which you use.

Figure 10-3: The GNU Emacs display in an X windowincludes pull-down menus for most common commands, includig save, search, undo, and help.

Figure 10-4: The XEmacs display in an X window includes a toolbar in addition to pull-down menus and a 3-D look to the interface.

If you get an error message when you try to run emacs , ask your system administrator what’s up. The emacs program may have another name on your system. If your system administrator says that you don’t have emacs , plead with him or her to get it.

If emacs looks or acts weird (weirder than usual, that is), your terminal type may not be set correctly. Again, ask your system administrator to straighten it out.

Tip To run XEmacs on the eating.peas file, type the command xemacs eating. peas.

Telling emacs what to do

Rather than have two modes, as does vi , emacs treats normal letters, numbers, and punctuation as text and sticks them in your file when you type them. (Pretty advanced concept, huh?) Commands are usually given by pressing combinations of the Ctrl (Control) key and a letter. You also give some commands by pressing the Meta key and a letter.

Tip On most computers, the Meta key is the Esc key. If your keyboard has an Alt key, it may be the Meta key. Try Alt to see whether it works. If it doesn’t, use Esc. Unlike with Alt, if you use Esc you must release the Esc key before you type the subsequent letter (Esc, release, letter). In the following section, we tell you to press Esc.

Another novel concept: Type to enter text

To enter text, just start typing! The text is inserted wherever your cursor is.

Getting around in emacs

To move the cursor around in your text, use these keys:

Arrow keys usually move the cursor up, down, left, and right.

Tip In a few situations, emacs doesn’t understand the arrow keys. If that’s true for you, press Ctrl+B to move backward one character, Ctrl+F to move forward one character, Ctrl+P to move to the preceding line, and Ctrl+N to move to the next line. At least they tried to make them mnemonic.

Ctrl+A moves to the beginning of the line.

Ctrl+E moves to the end of the line.

Esc+< (press Esc and then hold down Shift and press the comma key) moves to the beginning of the file.

Esc+> (press Esc and then hold down Shift and press the period key) moves to the end of the file.

Making changes in emacs

Even though emacs is a better text editor, you still make typos, change your mind, and think of brilliant improvements to your text. To change text, follow these steps:

Move the cursor to the beginning of the text you want to change.


Type the new text. The text is inserted wherever the cursor is.


Delete any text you don’t want.


It’s that simple. No weird commands required.

This command doesn’t save any changes you made to the file in emacs . It just gets you out. Some versions of emacs may ask whether you want to save the file the editor was looking at or say something like "Buffers not saved. Exit?" (Translation: "Do you really want to quit without saving your changes?") Press Y for yes or N for no, as appropriate. If you just want to get out, press N to the "Do you want to save" question or Y to the "Buffers not saved" question.

Deleting stuff in emacs

emacs has several commands for deleting stuff:

To delete the character the cursor is on, press Ctrl+D. Or, on many terminals, press the Del key.

To delete text from the cursor to the end of the word (up to a space or punctuation mark), press Esc and then D.

To delete from the cursor to the end of the line, press Ctrl+K.

Save that file before it’s too late!

To save the text in the file, press Ctrl+XS (press and hold down the Ctrl key, press X and S, and then release the Ctrl key). You should save your work every few minutes. Even though emacs isn’t as frustrating as vi (or ed , for that matter), lots can still go wrong.

Bidding emacs adieu

When you finish editing and want to leave emacs , press Ctrl+XC (press and hold down the Ctrl key, press X and C, and then release the Ctrl key). You leave emacs and see the UNIX shell prompt.
If you didn’t save your work, emacs politely points out that your buffers stuff you have been working on) aren’t saved and asks whether you really want to exit. It suggests pressing the n key as the safe default in case you want to return to emacs to save the file. To leave without saving, press the y key and then Enter.

It takes many fewer emacs commands to make a file and type some stuff, make a few changes, and then save the file and leave than it does with ed or vi . The emacs program has tons of commands, most of which are utterly useless. Table 10-2 lists the commonly used emacs commands.