2 .TH LESSKEY 1 "Version 581.2: 28 Apr 2021"
4 lesskey \- specify key bindings for less
6 .B "lesskey [\-o output] [\-\-] [input]"
8 .B "lesskey [\-\-output=output] [\-\-] [input]"
12 .B "lesskey \-\-version"
15 is used to specify a set of key bindings to be used by
17 The input file is a text file which describes the key bindings.
18 If the input file is "\-", standard input is read.
19 If no input file is specified, a standard filename is used
20 as the name of the input file, which depends on the system being used:
21 On Unix systems, "$HOME/.lesskey" is used;
22 on MS-DOS systems, "$HOME/_lesskey" is used;
23 and on OS/2 systems "$HOME/lesskey.ini" is used,
24 or "$INIT/lesskey.ini" if $HOME is undefined.
25 The output file is a binary file which is used by
27 If no output file is specified,
28 and the environment variable LESSKEY is set,
29 the value of LESSKEY is used as the name of the output file.
30 Otherwise, a standard filename is used as the name of the output file,
31 which depends on the system being used:
32 On Unix and OS-9 systems, "$HOME/.less" is used;
33 on MS-DOS systems, "$HOME/_less" is used;
34 and on OS/2 systems, "$HOME/less.ini" is used,
35 or "$INIT/less.ini" if $HOME is undefined.
36 If the output file already exists,
40 The \-V or \-\-version option causes
42 to print its version number and immediately exit.
43 If \-V or \-\-version is present, other options and arguments are ignored.
45 The input file consists of one or more
47 Each section starts with a line that identifies the type of section.
48 Possible sections are:
50 Defines new command keys.
52 Defines new line-editing keys.
54 Defines environment variables.
56 Blank lines and lines which start with a pound sign (#) are ignored,
57 except for the special section header lines.
60 The command section begins with the line
64 If the command section is the first section in the file,
65 this line may be omitted.
66 The command section consists of lines of the form:
68 \fIstring\fP <whitespace> \fIaction\fP [extra-string] <newline>
70 Whitespace is any sequence of one or more spaces and/or tabs.
71 The \fIstring\fP is the command key(s) which invoke the action.
72 The \fIstring\fP may be a single command key, or a sequence of up to 15 keys.
73 The \fIaction\fP is the name of the less action, from the list below.
74 The characters in the \fIstring\fP may appear literally, or be
75 prefixed by a caret to indicate a control key.
76 A backslash followed by one to three octal digits may be used to
77 specify a character by its octal value.
78 A backslash followed by certain characters specifies input
79 characters as follows:
109 A backslash followed by any other character indicates that character is
110 to be taken literally.
111 Characters which must be preceded by backslash include
112 caret, space, tab and the backslash itself.
114 An action may be followed by an "extra" string.
115 When such a command is entered while running
117 the action is performed, and then the extra
118 string is parsed, just as if it were typed in to
120 This feature can be used in certain cases to extend
121 the functionality of a command.
122 For example, see the "{" and ":t" commands in the example below.
123 The extra string has a special meaning for the "quit" action:
126 quits, the first character of the extra string is used as its exit status.
129 The following input file describes the set of
130 default command keys used by less:
166 \ee\e40 forw-screen-force
168 \eeF forw-until-hilite
201 \eeG goto-end-buffered
210 \een repeat-search-all
212 \eeN reverse-search-all
258 Commands specified by
260 take precedence over the default commands.
261 A default command key may be disabled by including it in the
262 input file with the action "invalid".
263 Alternatively, a key may be defined
264 to do nothing by using the action "noaction".
265 "noaction" is similar to "invalid", but
267 will give an error beep for an "invalid" command,
268 but not for a "noaction" command.
269 In addition, ALL default commands may be disabled by
270 adding this control line to the input file:
274 This will cause all default commands to be ignored.
275 The #stop line should be the last line in that section of the file.
277 Be aware that #stop can be dangerous.
278 Since all default commands are disabled,
279 you must provide sufficient commands before the #stop line
280 to enable all necessary actions.
281 For example, failure to provide a "quit" command can lead to frustration.
283 .SH "LINE EDITING SECTION"
284 The line-editing section begins with the line:
288 This section specifies new key bindings for the line editing commands,
289 in a manner similar to the way key bindings for
290 ordinary commands are specified in the #command section.
291 The line-editing section consists of a list of keys and actions,
292 one per line as in the example below.
295 The following input file describes the set of
296 default line-editing keys used by less:
321 \ee\eb word-backspace
334 .SH "LESS ENVIRONMENT VARIABLES"
335 The environment variable section begins with the line
339 Following this line is a list of environment variable assignments.
340 Each line consists of an environment variable name, an equals sign (=)
341 and the value to be assigned to the environment variable.
342 White space before and after the equals sign is ignored.
343 Variables assigned in this way are visible only to
345 If a variable is specified in the system environment and also in a
346 lesskey file, the value in the lesskey file takes precedence.
347 Although the lesskey file can be used to override variables set in the
348 environment, the main purpose of assigning variables in the lesskey file
349 is simply to have all
351 configuration information stored in one file.
354 The following input file sets the \-i option whenever
356 is run, and specifies the character set to be "latin1":
369 On MS-DOS and OS/2 systems, certain keys send a sequence of characters
370 which start with a NUL character (0).
371 This NUL character should be represented as \e340 in a lesskey file.
374 Copyright (C) 1984-2021 Mark Nudelman
376 less is part of the GNU project and is free software.
377 You can redistribute it and/or modify it
378 under the terms of either
379 (1) the GNU General Public License as published by
380 the Free Software Foundation; or (2) the Less License.
381 See the file README in the less distribution for more details
382 regarding redistribution.
383 You should have received a copy of the GNU General Public License
384 along with the source for less; see the file COPYING.
385 If not, write to the Free Software Foundation, 59 Temple Place,
386 Suite 330, Boston, MA 02111-1307, USA.
387 You should also have received a copy of the Less License;
388 see the file LICENSE.
390 less is distributed in the hope that it will be useful, but
391 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
392 or FITNESS FOR A PARTICULAR PURPOSE.
393 See the GNU General Public License for more details.
399 Report bugs at https://github.com/gwsw/less/issues.