Tag Archives: command

vi Editor: UNIX

vi is a command-line text editor originally created for the Unix operating system.

The name vi is derived from the shortest unambiguous abbreviation for the command visual; the command in question switches the line editor ex to visual mode.

Most of the network administrators are familiar with this little editor in Unix, because they use it regularly. But, for first timers, it’s most difficult editor. First timers have to remember all commands and keys to edit a simple file.

vi has two modes, Insert mode and Command mode. In insert mode, you can add/edit the texts in file. And in command mode, you can navigate and command the editor like save, exit, copy, paste, etc.

These are the commands and keys for those who want to get familiar with vi editor.

Command to open the vi editor:

vi filename

This command creates a new file if filename is not available in current directory. By default, vi begins in command mode.

To start the insert mode, you can use following keys:

Insert text at beginning of line:

I

Insert text at cursor:

i

append text after cursor:

a

Append text at line end:

A

Open line above cursor:

O

Open line below cursor:

o

To switching back, and start the Command mode, press [ESC]

Most commands execute as soon as typed except for “colon” commands which execute when you press the return key.

For cursor movement in command mode, you can use following commands/keys:

Go to beginning of line

0

Go to end of line

$

Go to line number ##

:##

Go to line n

nG

Go to last line

G

Left 6 chars

6h

Move left, down, up, right

h j k l

Move left, down, up, right

← ↓ ↑ →

Scroll Backward 1 screen

[ctrl] b

Scroll Forward 1 screen

[ctrl] f

Scroll by sentence forward/backward

( )

Scroll by word forward/backward

w b

Scroll by paragraph forward/backward

{ }

Scroll Up 1/2 screen

[ctrl] u

Scroll Down 1/2 screen

[ctrl] d

For deleting/changing text/character in command mode, you can use following commands/keys:

Change word

cw

Replace one character

r

Delete word

dw

Delete text at cursor

x

Delete entire line (to buffer)

dd

Delete (backspace) text at cursor

X

Delete 5 lines (to buffer)

5dd

Delete current to end of line

D

Delete lines 5-10

:5,10d

For editing content in command mode, you can use following commands/keys:

Copy line

yy

Copy n lines

nyy

Copy lines1-2 /paste after 3

:1,2t3

Move lines 4-5/paste after 6

:4,5m6

Paste above current line

P

Paste below current line

p

Undo all changes to line

U

Undo previous command

u

Join previous line

J

Find next string occurrence

n

Search backward for string

?string

Search forward forstring

/string

% (entire file) s (search and replace) /old text with new/ c (confirm) g (global – all)

:%s/oldstring/newstring/cg

Ignore case during search

:set ic

Repeat last command

.

For saving and quiting in command mode, you can use following commands/keys:

Save changes to buffer

:w

Save changes and quit vi

zz or :wq

Save file to new file

:w file

Quit without saving

:q!

Save lines to new file

:10,15w file

In all of the above commands, a number n will tell vi to repeat that command n times.

:syntax on Turn on syntax highlighting
:syntax off Turn off syntax highlighting
:set number Turn on Line numbering (shorthand :set nu)
:set nonumber Turn off Line numbering (shorthand :set nonu)

:set ignorecase Ignore case sensitivity when searching
:set noignorecase Restore case sensitivity (default)