The Incredibly Terse VI Manual

VI is a very powerful text editor that dates from the early days of Unix. It is also quite obscure in its workings. This "cheat sheet" summarizes the most common things you'll want to do in VI, and points the way to some of its more powerful capabilities.

To edit a file called "xyz", type: vi xyz

VI is a "two-mode" editor. When you type a character, it is either:

(mode 1) interpreted as a command (do thus-and-such), or

(mode 2) immediately inserted into the text of the file you are editing.

VI always starts in the first mode, called "command mode". Section 4 tells you how to switch to the other mode, called "insert" mode.. When in doubt, press the escape key (usually labeled "Esc" or "ESC"). This will put VI in the first, or "command" mode. If you are already in command mode, it will just beep at you. Ignore it.

Short Distances			Long Distances
h	move left one character
l	move right one character
j	move down one line		ctrl-F	move down ("forward") one screen
k	move up one line		ctrl-B	move up ("back") one screen
0	(zero) move to start of line		1G	move to the first line of the file
$	move to end of line		G	move to the last line of the file
Moving to Special Places			Text Searching
ma	mark this location as point "a"		/xyz	search for and move to next "xyz"
'a	move to previously marked "a"		n	move to next instance of search
%	move from "(" to matching ")"		N	move to previous instance of search

All of these commands switch VI from "command" mode to "insert" mode. Everything you type after this command gets inserted into the file. Press ESC to go back to command mode.

i insert text before cursor position

a insert ("append") text after cursor position

A insert text at the end of this line

Editing text			Editing the file
x	delete this character		:w	save your work
dd	delete this entire line		:q!	exit VI, don't save your work
D	delete from here to end of line		ZZ	save your work, and exit VI
u	undo last operation		:r abc	read in file abc after this line
.	do last operation again

You may perform more complicated operations on sets of lines in a file by using "ex" commands. All "ex" commands begin with a colon (":") and have the general form:

     :line1,line2,operation

5	(an actual number)
$	the last line of the file
.	the current line
'a	location "a" (from 'm' command)
.+1	line after this line
.-5	five lines back from this line

Operations include:

d	delete lines
m	move lines
t	transfer (copy) lines
s	substitute strings on lines

Examples:

:'a,.d	deletes lines between 'a and current line
:1,5t$	copies lines 1 through 5 to the end of the file
:1,$s/abc/gef/	substitutes first "abc" with "gef" in all lines
:1,$s/abc/gef/g	substitutes all "abc"s with "gef" in all lines
:8,10m12	moves lines 8 through 10 to after line 12
:.t.	duplicates current line

Certain characters, when used in between the slashes in the substitute ("s") command, have a special meaning. These characters are called "metacharacters". They are:

^	invisible character (or "anchor") before first character on line
$	invisible character (or "anchor") after last character on line
.	any single character
*	any number of the immediately preceeding character
[a-c]	any one character in the range a-c
\	escape next character to have normal meaning, e.g. "\$" is just a dollar sign.
&	replace with entire match string

Examples:

:1,$s/^/Hi! /
Puts "Hi! " at beginning of every line

:.s/a.b/ABC/
On current line, replace "a", any character, "b", with "ABC"

:1,$s/^.*$/& &/
Double contents of every line. That is, take each line, and append it to itself with a space in between. The ".*" matches any number of any character, and it's anchored on both ends so you get the entire line. Each "&" gets replaced with the entire match, so you end up "doubling" the entire line.