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Easy Editing: NEdit

Don't have time or interest to learn a Unix editor? ...then nedit is for you.

nedit belongs to the family of WYSIWYG (What You See Is What You Get) editors. Wysiwyg editors tend to be mouse-based and are easy to transition to if you have a stronger history with Macintosh or Windows editors. You can add text wherever the cursor is positioned and a swift hit of the delete key will remove any text that is highlighted. nedit offers extensive customization, even to the point of establishing automatic backups. There is a low- to no-learning curve with nedit. You can literally open a file and start working immediately with this editor.

The Essentials of Emacs

Starting the Emacs Program

     emacs file1.txt

If you are working remotely, the spawning of an external window may be problematic. If this is the case, you can startup emacs without generating an external window using:

     emacs -nw file1.txt

The Emacs Screen

Warning Unless you know what you are doing, avoid the Read Mail menu item in the Tools menu. This will allow you to read your email, but will save your mail in a file format indecipherable by any other known mail reader. Once in, this format, tedious human intervention is required to return your email to a more conventional format.

If you are editing a file in a complex language, for example TeX, there will also be menus specific to that language. Do explore this with a TeX file. You will be surprised at how well emacs becomes an integrated environment for previewing and printing, as well as editing, TeX.

Across the bottom of the screen is a black bar - the status bar. On the left side of the status bar is the name of the file you are editing. Next is the an indication of what sort of file emacs thinks you are editing (see the discussion of major and minor modes in the emacs online documentation for more on this. Emacs understands TeX, HTML, C, and a host of other languages besides plain text.)

Above the status bar is the edit pad - it contains the text of the file you are creating/editing.

Keyboard commands, the cornerstone of emacs' power, will appear in the command buffer, located below the status bar. This is one of the most important regions of the emacs window.

Entering Text

Basic Emacs Commands

All other emacs commands are entered via Control and Meta keys. For example, the command to save a file is Control-x Control-s (also written as C-x C-s). While holding down the Control key with your left hand, tap the x key (after a second or two, you will see C-x under the status bar). Then, while holding down the Control key with your left hand, tap the s key. While most keyboards have a Control key, most don't have an explicitly labeled Meta key. Often the Meta key is is the Alt key, which can be held down, but hitting the escape (labeled Esc) key briefly will always work. For example, to type Meta-x (also written M-x), you should either hold down the Alt key and tap the x key, or, if this doesn't work, tap the Esc key and then the x key.

Getting Help:

C-h

Enter the emacs Help system

C-h t

Enter the tutorial

C-h i

Enter the GNU info documentation system

C-h a

Apropos - find out about commands

C-b -or- / C-f -or-

Move one character backward / forward

M-b / M-f

Move one word backward / forward

C-p -or- / C-n -or-

Move one line backward / forward

M-a / M-e

Move one sentence backward / forward

C-v / M-v

Move one screen backward / forward

M-> / M-<

Move to the end / beginning of the file

DEL / C-d

Delete the previous / next character

M-DEL / M-d

Delete the previous / next word

C-x C-s

Save this file

C-x C-f

Close this file and open another file instead

C-x i

Insert another file into this one

C-x C-c

Quit emacs permanently

C-z

Suspend emacs temporarily (type fg to resume

C-s

Incremental search forward

C-r

Incremental search backward

Esc

Exit search

M-%

Query search and replace

C-_

Undo (That's an underscore, i.e shift -)

C-g

Abort current command

Reference Material

The Essentials of vi

vi (pronounced vee-eye - short for the word visual) - was the first Unix full-screen editor. Most UNIX users end up having to learn either vi or emacs. Neither program is particularly user-friendly, but vi is handy for quick editing sessions. Here is a brief lesson:

Starting the vi Program

   vi file1.txt

Sometimes, you may find yourself looking at a window which looks like:

Fundamentals

Command mode

here you give the text editing commands

Input mode

here you you type your text

Command Mode

There are several groups of commands, listed below. Most commands will take a numerical prefix; for example, 7w means ``jump ahead seven words'', and 3dd means ``delete the next three lines''. Note that you cannot enter any text until you switch to input mode. (This is not an exhaustive list of commands.)

Moving the Cursor:

h -or-

Move one character to the left

l -or-

(small ``ell'') Move one character to the right

j -or-

Move up one line

k -or-

Move down one line

w

Jump to the next word

b

Jump to the previous word

nG

Jump to line number n

$

Jump to the very end of the line

^

Jump to the very beginning of the line

G

Jump to the very end of the document

x

Delete this character

dw

Delete this word

dd

Delete this line

D

Delete the remainder of this line

r char

Replace this character with the character char

cw word

Replace this word with the word word

i

Input text in front of this character

a

Append text after this character

I

Input text in front of this line

A

Append text after this line

o

(small ``oh'') Open a new line underneath the current line

O

(capital ``oh'') Open a new line above the current line

R text

Replace the current text with text (i.e., obliterate current text)

Nyy

Yank (copy) N lines into a buffer

Ndd

Cut (remove) N lines into a buffer

p

Put the text from the buffer after this line

P

Put the text from the buffer before this line

:3,5s/foo/bar/g

Search lines 3-5 for all occurrences of foo and change them to bar. Without the trailing g this would only replace the first occurrence of foo on each line.

:1,$s/foo/bar/g

The same, but search through the whole document.

:3,5s/$/xyz/

Add the text xyz to the end of lines 3-5

:1,$s/^/xyz/

Add the text xyz to the beginning of every line in the document

:w

Save the current document

:wq

Save the current document, then quit vi

:q

Quit vi

:q!

Quit vi (without saving changes), even though you have changes to save

:e foo

Close the current document, and edit the file foo instead

u

Undo the last action

.

Repeat the last command action

/text

Jump ahead to the next occurrence of the string text in your document

?text

Jump back to the previous occurrence of the string text in your document

n

Repeat the last / or ? search

Input Mode

To switch back to command mode, press: Esc (escape).

Warning One of the most common errors in vi is to type a command while still in input mode. If you do this, the command will show up in the text! Remember, to type a command you must first return to command mode by pressing the Esc key.

Reference Material

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