lesskey
specify key bindings for less
see also :
less
Synopsis
lesskey [-o
output] [--] [input]
lesskey [--output=output] [--] [input]
lesskey -V
lesskey --version
add an example, a script, a trick and tips
examples
no example yet ...
... Feel free to add your own example above to help other Linux-lovers !
description
Lesskey
is used to specify a set of key bindings to be used by
less. The input file is a text file which describes
the key bindings. If the input file is "-",
standard input is read. If no input file is specified, a
standard filename is used as the name of the input file,
which depends on the system being used: On Unix systems,
$HOME/.lesskey is used; on MS-DOS systems, $HOME/_lesskey is
used; and on OS/2 systems $HOME/lesskey.ini is used, or
$INIT/lesskey.ini if $HOME is undefined. The output file is
a binary file which is used by less. If no output
file is specified, and the environment variable LESSKEY is
set, the value of LESSKEY is used as the name of the output
file. Otherwise, a standard filename is used as the name of
the output file, which depends on the system being used: On
Unix and OS-9 systems, $HOME/.less is used; on MS-DOS
systems, $HOME/_less is used; and on OS/2 systems,
$HOME/less.ini is used, or $INIT/less.ini if $HOME is
undefined. If the output file already exists, lesskey
will overwrite it.
The -V or
--version option causes lesskey to print its version
number and immediately exit. If -V or --version is present,
other options and arguments are ignored.
The input file
consists of one or more sections. Each section starts
with a line that identifies the type of section. Possible
sections are:
#command
Defines new command keys.
#line-edit
Defines new line-editing
keys.
#env
Defines environment variables.
Blank lines and
lines which start with a pound sign (#) are ignored, except
for the special section header lines.
command section
The command section begins with the line
#command
If the command section is the first section in the file, this
line may be omitted. The command section consists of lines of the
form:
string <whitespace> action [extra-string]
<newline>
Whitespace is any sequence of one or more spaces and/or tabs. The
string is the command key(s) which invoke the action. The
string may be a single command key, or a sequence of up to
15 keys. The action is the name of the less action, from
the list below. The characters in the string may appear
literally, or be prefixed by a caret to indicate a control key. A
backslash followed by one to three octal digits may be used to
specify a character by its octal value. A backslash followed by
certain characters specifies input characters as follows:
\b
BACKSPACE
\e
ESCAPE
\n
NEWLINE
\r
RETURN
\t
TAB
\ku
UP ARROW
\kd
DOWN ARROW
\kr
RIGHT ARROW
\kl
LEFT ARROW
\kU
PAGE UP
\kD
PAGE DOWN
\kh
HOME
\ke
END
\kx
DELETE
A backslash followed by any other character indicates that
character is to be taken literally. Characters which must be
preceded by backslash include caret, space, tab and the backslash
itself.
An action may be followed by an "extra" string. When such a
command is entered while running less, the action is
performed, and then the extra string is parsed, just as if it
were typed in to less. This feature can be used in certain
cases to extend the functionality of a command. For example, see
the "{" and ":t" commands in the example below. The extra string
has a special meaning for the "quit" action: when less
quits, first character of the extra string is used as its exit
status.
copyright
Copyright (C) 2000-2012 Mark Nudelman
lesskey is part of the GNU project and is free software; you can
redistribute it and/or modify it under the terms of the GNU
General Public License as published by the Free Software
Foundation; either version 2, or (at your option) any later
version.
lesskey is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with lesskey; see the file COPYING. If not, write to the
Free Software Foundation, 59 Temple Place, Suite 330, Boston, MA
02111-1307, USA.
example
The following input file sets the -i option whenever less
is run, and specifies the character set to be "latin1":
#env
LESS = -i
LESSCHARSET = latin1
less environment variables
The environment variable section begins with the line
#env
Following this line is a list of environment variable
assignments. Each line consists of an environment variable name,
an equals sign (=) and the value to be assigned to the
environment variable. White space before and after the equals
sign is ignored. Variables assigned in this way are visible only
to less. If a variable is specified in the system
environment and also in a lesskey file, the value in the lesskey
file takes precedence. Although the lesskey file can be used to
override variables set in the environment, the main purpose of
assigning variables in the lesskey file is simply to have all
less configuration information stored in one file.
line editing section
The line-editing section begins with the line:
#line-edit
This section specifies new key bindings for the line editing
commands, in a manner similar to the way key bindings for
ordinary commands are specified in the #command section. The
line-editing section consists of a list of keys and actions, one
per line as in the example below.
precedence
Commands specified by lesskey take precedence over the
default commands. A default command key may be disabled by
including it in the input file with the action "invalid".
Alternatively, a key may be defined to do nothing by using the
action "noaction". "noaction" is similar to "invalid", but
less will give an error beep for an "invalid" command, but
not for a "noaction" command. In addition, ALL default commands
may be disabled by adding this control line to the input file:
#stop
This will cause all default commands to be ignored. The #stop
line should be the last line in that section of the file.
Be aware that #stop can be dangerous. Since all default commands
are disabled, you must provide sufficient commands before the
#stop line to enable all necessary actions. For example, failure
to provide a "quit" command can lead to frustration.
warnings
On MS-DOS and OS/2 systems, certain keys send a sequence of
characters which start with a NUL character (0). This NUL
character should be represented as \340 in a lesskey file.
see also
less
author
Mark Nudelman
<bug-less[:at:]gnu[:dot:]org>
Send bug reports or comments to bug-less[:at:]gnu[:dot:]org.