DOC HOME SITE MAP MAN PAGES GNU INFO SEARCH PRINT BOOK
 
Editing files

Mapping key sequences

vi can assign sequences of commands to a series of keys or control characters so that whenever a mapped key sequence is typed, the command to which it is mapped is carried out. There are two commands to do this: :map, which works in command mode, and :map!, which works in insertion mode.

Assigning commands to a key sequence

To assign a command to a sequence of keystrokes, issue the :map! command in command mode. For example, to assign the command "ad$ to the key <Ctrl>C, you would enter the following:

:map ^C "ad$

^C is a <Ctrl>C character. (To enter the <Ctrl>C without letting vi interpret it, type <Ctrl>V<Ctrl>C.) This command cuts all text between the current cursor position and the end of the line, and places it in buffer ``a''. Now, whenever you type <Ctrl>C in command mode, it will carry out the defined series of commands.


NOTE: It is a bad idea to assign mappings to key sequences that are already in use as commands, because it renders the commands inaccessible.

Assigning insertions to a key sequence

To assign a key mapping in insertion mode, go to command mode and issue the :map! command. For example, to make the sequence ``EC'' map to ``European Community'', enter:

:map! EC European Community

To remove a mapping from a key, use the unmap (or :unmap!) command; for example:

:unmap ^C
:unmap! EC

When you begin to type a letter that may be part of a mapped command, vi saves up your typed input and checks whether it matches a mapping before it does anything. If the key sequence you type is a mapped command, vi executes it as soon as the command is complete; if not, when it becomes clear that you are not typing a mapped key sequence, vi acts on the keystrokes. (vi waits for a period of time that you can alter by resetting the timeout internal variable. See the vi(1) manual page for further details. The ab command works in a different manner described by ``Defining abbreviations''.)

To stop vi from expanding a mapping, you must escape the first character of the command before you begin typing. For example, using the mapping above, to enter the acronym ``EC'' you must escape the mapped word by entering:

<Ctrl>VEC

(If you had used an abbreviation for ``ma1G'' instead of a mapping, you would have to type the following to escape it:

ma1G<Ctrl>V


NOTE: Never define a mapping that contains its own name.

For example, consider the following bad definition:

:map! n banana

If you were to try this example, the next time you typed the letter ``n'' vi would expand it to ``banana''. But it would only get as far as the third character in ``banana'' before it saw another ``n'' and tried to expand it. The process produces output like:

bababababababababababababababababa

vi begins to execute the mapping then dies.

Changing modes within a mapped command

Sometimes it is useful to create a mapping or command that changes mode while it runs. For example, to create a command-mode mapping that inserts a piece of text under the cursor without leaving command mode, do this:

:map h iHello there!^[

The ``^['' character means ``escape''. To enter it into a mapping without letting vi act on it as if it is a command, press <Ctrl>V<Esc>.

When you press ``h'' in command mode, vi carries out the actions in the mapping. It executes the command i and switches to insert mode, enters the characters ``Hello there!'', then switches back to command mode on encountering the Esc character in the sequence of keys.

For example, suppose you have stored your name and address in a file called .address in your home directory. You can define a mapping that will automatically insert the contents of .address at the beginning of a file you are editing. For example, if your login is roberta, the mapping would be:

:map % ma1G^:0r /u/roberta/.address^M`a

When you type the ``%'' key in command mode, the first command, ma, marks your current position in the file with marker ``a''. The next commands, 1G^, go to line one of the file, then to the beginning of that line. The following command reads in the file /u/roberta/.address at the current location:

:r /u/roberta/.address^M

The mapping ends with the command `a, which returns to marker ``a''.

Note that ^M is a carriage return character entered into your mapping by pressing <Ctrl>V<Enter>.

Now whenever you type the ``%'' key in command mode, vi executes the command sequence to insert /u/roberta/.address at the top of your file.


© 2004 The SCO Group, Inc. All rights reserved.
UnixWare 7 Release 7.1.4 - 22 April 2004