Configuring vi

vi has a number of internal variables. These can be configured by typing the :setvarname command, where varname is the name of the variable to change.

To examine vi's current settings, go to command mode and type :set all.

If a variable name starts with ``no'', it is not set (that is, not switched on). You can set it by typing :set varname, with an optional value. If a variable name does not start with ``no'', and is not followed by a number, it is set. You can switch it off by issuing a command like :set novarname. For example, to make vi ignore wildcards, you must switch off the variable ``magic''. To do this, type :set nomagic.

To make vi automatically begin a new line before you reach the right-hand side of the screen, type :set wrapmargin=15. The first word that is less than fifteen characters from the right-hand side of the screen is placed on a new line. (If you have used word processors, this feature may be known to you as ``word wrap''.)

Here are some of the most useful vi settings. Some of them can be abbreviated; for example, typing :set autowrite and :set aw have the same effect.

number

Displays line numbers at the left-hand edge of the screen. (The numbers are not part of the saved file). You can go to any line by going to command mode and entering the line number followed by G. (This setting can be abbreviated to nu.)

autoindent

Indents the left-hand margin of new lines of text by an amount determined from the previous line of text. For example, if you indent a line by one tab, vi will automatically indent all subsequent lines by the same distance until you cancel the previous indent by pressing <Ctrl>D. (This setting can be abbreviated to ai.)

autowrite

Saves any changes that have been made to the current file when you issue a :n, :rew, or :! command. (This setting can be abbreviated to aw.)

ignorecase

Ignores the case of text while searching. (This setting can be abbreviated to ic.)

list

Prints end-of-line characters as ``$'', and tab characters as ``^I''. These characters are normally invisible.

showmode

Displays a message at the bottom right of the screen when you switch to a text input mode.

tabstop

Sets the number of spaces between each tab stop on the screen. When you press the <Tab> key in insertion mode, you are inserting a special tab character into your text. vi interprets this as a command to replace the tab character with however many spaces are needed to bring the cursor into line with the next tab stop position. vi normally puts tab stops eight characters apart; by using :set tabstop=number you can change the number of characters between tabs. This is useful for adjusting the width of columns of text or levels of indentation in documents created using tabs instead of spaces. (This setting can be abbreviated to ts.)

You can create a list of these variables that are automatically set whenever you start vi as described in the following section.