Linux vi commands : Tutorials-3

The default editor that comes with the UNIX operating system is called vi (visual editor).

To Start vi

To use vi on a file, type in vi filename. If the file named filename exists, then the first page (or screen) of the file will be displayed; if the file does not exist, then an empty file and screen are created into which you may enter text.
* vi filename edit filename starting at line 1
  vi -r filename recover filename that was being edited when system crashed

To Exit vi

Usually the new or modified file is saved when you leave vi. However, it is also possible to quit vi without saving the file.
Note: The cursor moves to bottom of screen whenever a colon (:) is typed. This type of command is completed by hitting the <Return> (or <Enter>) key.
* :x <Return> quit vi, writing out modified file to file named in original invocation
  :wq<Return> quit vi, writing out modified file to file named in original invocation
  :q<Return> quit (or exit) vi
* :q!<Return> quit vi even though latest changes have not been saved for this vi call

Adding, Changing, and Deleting Text

Unlike PC editors, you cannot replace or delete text by highlighting it with the mouse. Instead use the commands in the following tables.
Perhaps the most important command is the one that allows you to back up and undo your last action. Unfortunately, this command acts like a toggle, undoing and redoing your most recent action. You cannot go back more than one step.
* u UNDO WHATEVER YOU JUST DID; a simple toggle
The main purpose of an editor is to create, add, or modify text for a file.

Inserting or Adding Text

The following commands allow you to insert and add text. Each of these commands puts the vi editor into insert mode; thus, the <Esc> key must be pressed to terminate the entry of text and to put the vi editor back into command mode.
* i insert text before cursor, until <Esc> hit
  I insert text at beginning of current line, until <Esc> hit
* a append text after cursor, until <Esc> hit
  A append text to end of current line, until <Esc> hit
* o open and put text in a new line below current line, until <Esc> hit
* O open and put text in a new line above current line, until <Esc> hit

Changing Text

The following commands allow you to modify text.
* r replace single character under cursor (no <Esc> needed)
  R replace characters, starting with current cursor position, until <Esc> hit
  cw change the current word with new text,
starting with the character under cursor, until
<Esc> hit
  cNw change N words beginning with character under cursor, until <Esc> hit;
  e.g.,
c5w changes 5 words
  C change (replace) the characters in the current line, until <Esc> hit
  cc change (replace) the entire current line, stopping when <Esc> is hit
  Ncc or cNc change (replace) the next N lines, starting with the current line,
stopping when
<Esc> is hit

Deleting Text

The following commands allow you to delete text.
* x delete single character under cursor
  Nx delete N characters, starting with character under cursor
  dw delete the single word beginning with character under cursor
  dNw delete N words beginning with character under cursor;
  e.g.,
d5w deletes 5 words
  D delete the remainder of the line, starting with current cursor position
* dd delete entire current line
  Ndd or dNd delete N lines, beginning with the current line;
  e.g.,
5dd deletes 5 lines

Cutting and Pasting Text

The following commands allow you to copy and paste text.
  yy copy (yank, cut) the current line into the buffer
  Nyy or yNy copy (yank, cut) the next N lines, including the current line, into the buffer
  p put (paste) the line(s) in the buffer into the text after the current line

This entry was posted in Programing, Unix and tagged . Bookmark the permalink.

Leave a Reply

Your email address will not be published. Required fields are marked *

*

You may use these HTML tags and attributes: <a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>