How to use vi editor?

Linux peoples commonly use vi editor. vi/vim editor is a command line editor. Vim is a text editor that is upwards compatible to Vi. It can be used to edit all kinds of plain text. It is especially useful for editing programs.

Starting vi/vim

# vi filename  edit a file named "filename" 
# vi newfile  create a new file named "newfile"

ENTERING TEXT

i  insert text left of cursor
a  append text right of cursor

MOVING THE CURSOR

h  left one space 
j  down one line 
k  up one line 
l  right one space

BASIC EDITING

x  delete character 
nx  delete n characters 
X  delete character before cursor 
dw  delete word 
ndw  delete n words 
dd  delete line 
ndd  delete n lines 
D  delete characters from cursor to end of line 
r  replace character under cursor 
cw  replace a word ncw replace n words 
C  change text from cursor to end of line 
o  insert blank line below cursor (ready for insertion) 
O  nsert blank line above cursor (ready for insertion) 
J  join succeeding line to current cursor line 
nJ  join n succeeding lines to current cursor line 
u  undo last change 
U  restore current line
p  paste copy line
5yy  copy five line

MOVING AROUND IN A FILE

w  forward word by word 
b  backward word by word 
$  to end of line 
0  to beginning of line 
H  to top line of screen 
M  to middle line of screen 
L  to last line of screen 
G  to last line of file 
1G  to first line of file
<Control>f scroll forward one screen
<Control>b scroll backward one screen
<Control>d scroll down one-half screen
<Control>u scroll up one-half screen 
n  repeat last search in same direction 
N  repeat last search in opposite direction

CLOSING AND SAVING A FILE

ZZ  save file and then quit
:w  save file
:q!  discard changes and quit file

SEARCHING and REPLACING

The formal syntax for searching is:

:s/string

The syntax for replacing one string with another string in the current line is

:s/pattern/replace/

Here “pattern” represents the old string and “replace” represents the new string.

The syntax for replacing occurrence of a string in the text is similar. The only difference is the addition of a “%” in front of the “s”:

:%s/pattern/replace/
:%s/http:\/\/localhost/http:\/\/devopsfunda.com

To undo recent changes, from normal mode use the undo command:

u undo last change (can be repeated to undo preceding commands)

Ctrl-R Redo changes which were undone (undo the undos). Compare to . to a previous change, at the current cursor position. Ctrl-R (hold down Ctrl and press r) will redo a previously undone change, wherever the change occurred.