How Do I Use VI?

Article courtesy Pat Palmer for her CIT 593 students

In VI, you're always in one of three modes:

1. navigation - moving the cursor around with the h, j, k, l keys
2. insert - whatever you type gets inserted into the file
   (hit ESC to get back to navigation mode)
3. command - you have entered a : character, preceding a command string
   (hit [return] or [esc][esc] to get back to navigation mode)

General Startup

To use vi:	vi filename
To exit and save changes:	:wq!
To exit without saving changes:	:q!
To save changes without quitting:	:w!
To get out of insert mode:	[esc]

Cursor Movement

h	move left (backspace)
j	move down
k	move up
l	move right

NOTE: A number can precede any VI command to tell VI to repeat that command that many times.
EXAMPLES:

j	moves down 1 line
3j	moves down 3 lines
30j	moves down 30 lines
10k	moves up 10 lines

SHOW CURRENT LINE

:.=

MOVING AROUND QUICKLY

:#	move to line #
:$	move to last line of file

EXAMPLES:

:1	moves to first line of file
:5	moves to 5th line of file

Inserting

i	insert before cursor
o	open a line below cursor and enter insert mode at beginning of line
O	open a line above cursor and enter insert mode at beginning of line

Deleting (Yanking)

x	delete character under cursor
dd	delete (yank) line under cursor

EXAMPLE:

5dd	yanks 5 lines
p	puts them back (below current cursor)

Restoring (Putting)

p	puts last thing yanked to right of cursor

Copying Code

yy	(yank)'copies' line which may then be put by the p(put) command. <-- Precede with a number for multiple lines

Put Command

brings back previous deletion or yank of lines

P	bring back before cursor
p	bring back after cursor

Find Commands

?	finds a word going backwards
/	finds a word going forwards

Replace String

:1,$s/newstring/oldstring/g	from columns 1 to last ($), substitute globally (all lines)
:1,$s/newstring/oldstring/	from columns 1 to last ($), substitute from cursor forwards
:1,10s/newstring/oldstring/g	from columns 1 to 10, substitute globally (all lines)

SPECIAL COLUMN DESIGNATORS IN REPLACE:

$	last column on the current line
^	first column on the current line

Delete unwanted control characters from a Windows text file

:1,$s/^M//g

from line 1 to last line ($), get rid of the Control-M (carriage return)

NOTE: to enter ^M above, first enter [control-V], to get into the mode expecting control char, followed immediately by [control-M]

Miscellaneous Commands

.	repeat last command
u	undoes last command issued
J	join current line with the next line
^G	display current line number

READING (IMPORTING) FILES

:r filename

copies (reads) filename into current file after cursor

TO COPY PART OF ONE FILE TO ANOTHER FILE:

1. vi file1 file2    (this puts into file1 first)
2. copy lines from file1 (yank and put them back)
3. from file1, enter :n! to move to next file
4. put the lines into the next file

SHELL ESCAPE

:!'cmd'

executes 'cmd' as a shell command.