NAME
lesskey
—
specify key bindings for
less
SYNOPSIS
lesskey |
[-o output |
--output =output]
[input] |
lesskey |
-V | --version |
DESCRIPTION
lesskey
is used to specify a set of key
bindings to be used by
less(1). 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; by default $HOME/.lesskey. The output
file is a binary file which is used by
less(1). 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; by
default $HOME/.less is used. If the output file
already exists, lesskey
will overwrite it.
A system-wide lesskey file may also be set up to provide key
bindings. If a key is defined in both a local lesskey file and in the
system-wide file, key bindings in the local file take precedence over those
in the system-wide file. If the environment variable
LESSKEY_SYSTEM
is set,
less(1) uses that as the name of the system-wide lesskey file.
Otherwise, less(1) looks in a standard place for the system-wide lesskey
file: On OpenBSD, the system-wide lesskey file is
/etc/sysless.
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:
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 additional 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 into 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, the first
character of the extra string is used as its exit status.
The following input file describes the set of default command keys used by less:
#command \r forw-line \n forw-line e forw-line j forw-line \kd forw-line ^E forw-line ^N forw-line k back-line y back-line ^Y back-line ^K back-line ^P back-line J forw-line-force K back-line-force Y back-line-force d forw-scroll ^D forw-scroll u back-scroll ^U back-scroll \40 forw-screen f forw-screen ^F forw-screen ^V forw-screen \kD forw-screen b back-screen ^B back-screen \ev back-screen \kU back-screen z forw-window w back-window \e\40 forw-screen-force F forw-forever \eF forw-until-hilite R repaint-flush r repaint ^R repaint ^L repaint \eu undo-hilite g goto-line \kh goto-line < goto-line \e< goto-line p percent % percent \e[ left-scroll \e] right-scroll \e( left-scroll \e) right-scroll { forw-bracket {} } back-bracket {} ( forw-bracket () ) back-bracket () [ forw-bracket [] ] back-bracket [] \e^F forw-bracket \e^B back-bracket G goto-end \e> goto-end > goto-end \ke goto-end = status ^G status :f status / forw-search ? back-search \e/ forw-search * \e? back-search * n repeat-search \en repeat-search-all N reverse-search \eN reverse-search-all & filter m set-mark ´ goto-mark ^X^X goto-mark E examine :e examine ^X^V examine :n next-file :p prev-file t next-tag T prev-tag :x index-file :d remove-file - toggle-option :t toggle-option t s toggle-option o _ display-option | pipe v visual ! shell + firstcmd H help h help V version 0 digit 1 digit 2 digit 3 digit 4 digit 5 digit 6 digit 7 digit 8 digit 9 digit q quit Q quit :q quit :Q quit ZZ quit
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.
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.
The following input file describes the set of default line-editing keys used by less:
#line-edit \t forw-complete \17 back-complete \e\t back-complete ^L expand ^V literal ^A literal \el right \kr right \eh left \kl left \eb word-left \e\kl word-left \ew word-right \e\kr word-right \ei insert \ex delete \kx delete \eX word-delete \ekx word-delete \e\b word-backspace \e0 home \kh home \e$ end \ke end \ek up \ku up \ej down ^G abort
ENVIRONMENT SECTION
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. Whitespace before and after the equals sign is ignored. Variables assigned in this way are visible only to less. If environment variables are defined in more than one place, variables defined in a local lesskey file take precedence over variables defined in the system environment, which take precedence over variables defined in the system-wide lesskey file. 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.
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
ENVIRONMENT
LESSKEY
- Name of the default
lesskey
file. LESSKEY_SYSTEM
- Name of the default system-wide
lesskey
file.
FILES
- $HOME/.less
- Default
lesskey
file. - $HOME/.lesskey
- Default
lesskey
input file. - /etc/sysless
- Default system-wide
lesskey
file.
SEE ALSO
AUTHORS
Mark Nudelman
Send bug reports or comments to <bug-less@gnu.org>.