The traditional editor for unix is vi (for visual ).

Vi is a dual-mode editor; one switches from command mode to edit mode, so the effect of any key depends on the context. To edit a file xxx (or to create it in the first place), the command is vi xxx .

Vi starts in the command mode; you will likely want to position the cursor (h, j, k, l) and enter insert mode (i). You can then type. To leave insert mode, press Esc ; to write the file and quit the editor type :wq and press Enter.

Here is a summary of the commands. Note that it is necessary to press Escape to leave any of the open-ended editing modes (for example, i is open-ended, but r is not). The Escape key is a general-purpose reset. The only consequence of pressing escape too many times is a beep.

Essential vi

Commands :q quit
:wq write, then quit
:q! quit, discard changes
:w name write under a new name
Esc reset (leave input mode)
There are two definitions of ___word___
  1. letters, digits, underscore, surrounded by others
  2. anything surrounded by space
h, j, k, l left, down, up, right
0, ^, $ start, first nonblank position, end of line
Enter, - move one line
^D, ^U move half page
^F, ^B move full page
###G go to line ###
G go to bottom
^L redraw
Esc reset
w, W forward word (1) or word (2).
b, B backward word
e, E end of word
H, M, L home, mid screen, lower screen
Editing i, a insert before (append after) cursor
I, A insert at start of (append to) line
x, X delete at (before) cursor
o, O open line after (before) current line
dd delete a line
cc change a line
cw change a word
r change (replace) one character
R overwrite (until reset)
s substitute for this character
S substitute for this line
J join next line to this
u undo last change to the line
U undo all changes to the line
yy yank (paste in) line
p put line
Sentences >, < forward, backward
Find fx, Fx find character 'x' forward, backward
find next
tx, Tx like f,F but stop one character short.
/xxx forward search for xxx.
?xxx backward search for xxx.

A.E. Dec 2013