lesskey(1) — Linux manual page


LESSKEY(1)               General Commands Manual              LESSKEY(1)

NAME         top

       lesskey - specify key bindings for less

SYNOPSIS (deprecated)         top

       lesskey [-o output] [--] [input]
       lesskey [--output=output] [--] [input]
       lesskey -V
       lesskey --version

SCOPE         top

       This document describes the format of the lesskey source file,
       which is used by less version 582 and later.  In previous
       versions of less, a separate program called lesskey was used to
       compile the lesskey source file into a format understood by less.
       This compilation step is no longer required and the lesskey
       program is therefore deprecated although the file format remains
       supported by less itself.

FILE FORMAT         top

       The input file consists of one or more sections.  Each section
       starts with a line that identifies the type of section.  Possible
       sections are:

              Defines new command keys.

              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.


       The command section begins with the line


       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

       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, the first
       character of the extra string is used as its exit status.

EXAMPLE         top

       The following input file describes the set of default command
       keys used by less:

            \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
            \eU        clear-search
            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
            \kl        left-scroll
            \kr        right-scroll
            \e{        no-scroll
            \e}        end-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
            \eG        goto-end-buffered
            =          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
            M          set-mark-bottom
            \em        clear-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         top

       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:


       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.


       The line-editing section begins with the line:


       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.

EXAMPLE         top

       The following input file describes the set of default line-
       editing keys used by less:

            \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


       The environment variable section begins with the line


       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.

EXAMPLE         top

       The following input file sets the -i option whenever less is run,
       and specifies the character set to be "latin1":

                 LESS = -i
                 LESSCHARSET = latin1

SEE ALSO         top


WARNINGS         top

       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.

COPYRIGHT         top

       Copyright (C) 1984-2021  Mark Nudelman

       less is part of the GNU project and is free software.  You can
       redistribute it and/or modify it under the terms of either (1)
       the GNU General Public License as published by the Free Software
       Foundation; or (2) the Less License.  See the file README in the
       less distribution for more details regarding redistribution.  You
       should have received a copy of the GNU General Public License
       along with the source for less; see the file COPYING.  If not,
       write to the Free Software Foundation, 59 Temple Place, Suite
       330, Boston, MA  02111-1307, USA.  You should also have received
       a copy of the Less License; see the file LICENSE.

       less is distributed in the hope that it will be useful, but
       WITHOUT ANY WARRANTY; without even the implied warranty of
       General Public License for more details.

AUTHOR         top

       Mark Nudelman
       Report bugs at https://github.com/gwsw/less/issues.

COLOPHON         top

       This page is part of the less (A file pager) project.
       Information about the project can be found at 
       ⟨http://www.greenwoodsoftware.com/less/⟩.  If you have a bug
       report for this manual page, see
       ⟨http://www.greenwoodsoftware.com/less/faq.html#bugs⟩.  This page
       was obtained from the tarball less-590.tar.gz fetched from
       ⟨http://www.greenwoodsoftware.com/less/download.html⟩ on
       2021-08-27.  If you discover any rendering problems in this HTML
       version of the page, or you believe there is a better or more up-
       to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not
       part of the original manual page), send a mail to

                        Version 590: 03 Jun 2021              LESSKEY(1)

Pages that refer to this page: less(1)