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less(1)                     General Commands Manual                    less(1)


NAME

       less - display the contents of a file in a terminal


SYNOPSIS

       less -?
       less --help
       less -V
       less --version
       less [-[+]aABcCdeEfFgGiIJKLmMnNqQrRsSuUVwWX~]
            [-b space] [-h lines] [-j line] [-k keyfile]
            [-{oO} logfile] [-p pattern] [-P prompt] [-t tag]
            [-T tagsfile] [-x tab,...] [-y lines] [-[z] lines]
            [-# shift] [+[+]cmd] [--] [filename]...
       (See the OPTIONS section for alternate option syntax with long option
       names.)


DESCRIPTION

       Less is a program similar to more(1), but it has many more features.
       Less does not have to read the entire input file before starting, so
       with large input files it starts up faster than text editors like
       vi(1).  Less uses termcap (or terminfo on some systems), so it can run
       on a variety of terminals.  There is even limited support for hardcopy
       terminals.  (On a hardcopy terminal, lines which should be printed at
       the top of the screen are prefixed with a caret.)

       Commands are based on both more and vi.  Commands may be preceded by a
       decimal number, called N in the descriptions below.  The number is used
       by some commands, as indicated.


COMMANDS

       In the following descriptions, ^X means control-X.  ESC stands for the
       ESCAPE key; for example ESC-v means the two character sequence
       "ESCAPE", then "v".

       h or H Help: display a summary of these commands.  If you forget all
              the other commands, remember this one.

       SPACE or ^V or f or ^F
              Scroll forward N lines, default one window (see option -z
              below).  If N is more than the screen size, only the final
              screenful is displayed.  Warning: some systems use ^V as a
              special literalization character.

       z      Like SPACE, but if N is specified, it becomes the new window
              size.

       ESC-SPACE
              Like SPACE, but scrolls a full screenful, even if it reaches
              end-of-file in the process.

       ENTER or RETURN or ^N or e or ^E or j or ^J
              Scroll forward N lines, default 1.  The entire N lines are
              displayed, even if N is more than the screen size.

       d or ^D
              Scroll forward N lines, default one half of the screen size.  If
              N is specified, it becomes the new default for subsequent d and
              u commands.

       b or ^B or ESC-v
              Scroll backward N lines, default one window (see option -z
              below).  If N is more than the screen size, only the final
              screenful is displayed.

       w      Like ESC-v, but if N is specified, it becomes the new window
              size.

       y or ^Y or ^P or k or ^K
              Scroll backward N lines, default 1.  The entire N lines are
              displayed, even if N is more than the screen size.  Warning:
              some systems use ^Y as a special job control character.

       u or ^U
              Scroll backward N lines, default one half of the screen size.
              If N is specified, it becomes the new default for subsequent d
              and u commands.

       J      Like j, but continues to scroll beyond the end of the file.

       K or Y Like k, but continues to scroll beyond the beginning of the
              file.

       ESC-) or RIGHTARROW
              Scroll horizontally right N characters, default half the screen
              width (see the -# option).  If a number N is specified, it
              becomes the default for future RIGHTARROW and LEFTARROW
              commands.  While the text is scrolled, it acts as though the -S
              option (chop lines) were in effect.

       ESC-( or LEFTARROW
              Scroll horizontally left N characters, default half the screen
              width (see the -# option).  If a number N is specified, it
              becomes the default for future RIGHTARROW and LEFTARROW
              commands.

       ESC-} or ^RIGHTARROW
              Scroll horizontally right to show the end of the longest
              displayed line.

       ESC-{ or ^LEFTARROW
              Scroll horizontally left back to the first column.

       r or ^R or ^L
              Repaint the screen.

       R      Repaint the screen, discarding any buffered input.  That is,
              reload the current file.  Useful if the file is changing while
              it is being viewed.

       F      Scroll forward, and keep trying to read when the end of file is
              reached.  Normally this command would be used when already at
              the end of the file.  It is a way to monitor the tail of a file
              which is growing while it is being viewed.  (The behavior is
              similar to the "tail -f" command.)  To stop waiting for more
              data, enter the interrupt character (usually ^C).  On systems
              which support poll(2) you can also use ^X or the character
              specified by the --intr option.  If the input is a pipe and the
              --exit-follow-on-close option is in effect, less will
              automatically stop waiting for data when the input side of the
              pipe is closed.

       ESC-F  Like F, but as soon as a line is found which matches the last
              search pattern, the terminal bell is rung and forward scrolling
              stops.

       g or < or ESC-<
              Go to line N in the file, default 1 (beginning of file).
              (Warning: this may be slow if N is large.)

       G or > or ESC->
              Go to line N in the file, default the end of the file.
              (Warning: this may be slow if N is large, or if N is not
              specified and standard input, rather than a file, is being
              read.)

       ESC-G  Same as G, except if no number N is specified and the input is
              standard input, goes to the last line which is currently
              buffered.

       p or % Go to a position N percent into the file.  N should be between 0
              and 100, and may contain a decimal point.

       P      Go to the line containing byte offset N in the file.

       {      If a left curly bracket appears in the top line displayed on the
              screen, the { command will go to the matching right curly
              bracket.  The matching right curly bracket is positioned on the
              bottom line of the screen.  If there is more than one left curly
              bracket on the top line, a number N may be used to specify the
              N-th bracket on the line.

       }      If a right curly bracket appears in the bottom line displayed on
              the screen, the } command will go to the matching left curly
              bracket.  The matching left curly bracket is positioned on the
              top line of the screen.  If there is more than one right curly
              bracket on the bottom line, a number N may be used to specify
              the N-th bracket on the line.

       (      Like {, but applies to parentheses rather than curly brackets.

       )      Like }, but applies to parentheses rather than curly brackets.

       [      Like {, but applies to square brackets rather than curly
              brackets.

       ]      Like }, but applies to square brackets rather than curly
              brackets.

       ESC-^F Followed by two characters, acts like {, but uses the two
              characters as open and close brackets, respectively.  For
              example, "ESC ^F < >" could be used to go forward to the > which
              matches the < in the top displayed line.

       ESC-^B Followed by two characters, acts like }, but uses the two
              characters as open and close brackets, respectively.  For
              example, "ESC ^B < >" could be used to go backward to the <
              which matches the > in the bottom displayed line.

       m      Followed by any lowercase or uppercase letter, marks the first
              displayed line with that letter.  If the status column is
              enabled via the -J option, the status column shows the marked
              line.

       M      Acts like m, except the last displayed line is marked rather
              than the first displayed line.

       '      (Single quote.)  Followed by any lowercase or uppercase letter,
              returns to the position which was previously marked with that
              letter.  Followed by another single quote, returns to the
              position at which the last "large" movement command was
              executed.  Followed by a ^ or $, jumps to the beginning or end
              of the file respectively.  Marks are preserved when a new file
              is examined, so the ' command can be used to switch between
              input files.

       ^X^X   Same as single quote.

       ESC-m  Followed by any lowercase or uppercase letter, clears the mark
              identified by that letter.

       /pattern
              Search forward in the file for the N-th line containing the
              pattern.  N defaults to 1.  The pattern is a regular expression,
              as recognized by the regular expression library supplied by your
              system.  By default, searching is case-sensitive (uppercase and
              lowercase are considered different); the -i option can be used
              to change this.  The search starts at the first line displayed
              (but see the -a and -j options, which change this).

              Certain characters are special if entered at the beginning of
              the pattern; they modify the type of search rather than become
              part of the pattern:

              ^N or !
                     Search for lines which do NOT match the pattern.

              ^E or *
                     Search multiple files.  That is, if the search reaches
                     the END of the current file without finding a match, the
                     search continues in the next file in the command line
                     list.

              ^F or @
                     Begin the search at the first line of the FIRST file in
                     the command line list, regardless of what is currently
                     displayed on the screen or the settings of the -a or -j
                     options.

              ^K     Highlight any text which matches the pattern on the
                     current screen, but don't move to the first match (KEEP
                     current position).

              ^R     Don't interpret regular expression metacharacters; that
                     is, do a simple textual comparison.

              ^S     Followed by a digit N between 1 and 5.  Only text which
                     has a non-empty match for the N-th parenthesized SUB-
                     PATTERN will be considered to match the pattern.
                     (Supported only if less is built with one of the regular
                     expression libraries posix, pcre, or pcre2.) Multiple ^S
                     modifiers can be specified, to match more than one sub-
                     pattern.

              ^W     WRAP around the current file.  That is, if the search
                     reaches the end of the current file without finding a
                     match, the search continues from the first line of the
                     current file up to the line where it started.  If the ^W
                     modifier is set, the ^E modifier is ignored.

              ^L     The next character is taken literally; that is, it
                     becomes part of the pattern even if it is one of the
                     above search modifier characters.

       ?pattern
              Search backward in the file for the N-th line containing the
              pattern.  The search starts at the last line displayed (but see
              the -a and -j options, which change this).

              Certain characters are special as in the / command:

              ^N or !
                     Search for lines which do NOT match the pattern.

              ^E or *
                     Search multiple files.  That is, if the search reaches
                     the beginning of the current file without finding a
                     match, the search continues in the previous file in the
                     command line list.

              ^F or @
                     Begin the search at the last line of the last file in the
                     command line list, regardless of what is currently
                     displayed on the screen or the settings of the -a or -j
                     options.

              ^K     As in forward searches.

              ^R     As in forward searches.

              ^S     As in forward searches.

              ^W     WRAP around the current file.  That is, if the search
                     reaches the beginning of the current file without finding
                     a match, the search continues from the last line of the
                     current file up to the line where it started.

       ESC-/pattern
              Same as "/*".

       ESC-?pattern
              Same as "?*".

       n      Repeat previous search, for N-th line containing the last
              pattern.  If the previous search was modified by ^N, the search
              is made for the N-th line NOT containing the pattern.  If the
              previous search was modified by ^E, the search continues in the
              next (or previous) file if not satisfied in the current file.
              If the previous search was modified by ^R, the search is done
              without using regular expressions.  There is no effect if the
              previous search was modified by ^F or ^K.

       N      Repeat previous search, but in the reverse direction.

       ESC-n  Repeat previous search, but crossing file boundaries.  The
              effect is as if the previous search were modified by *.

       ESC-N  Repeat previous search, but in the reverse direction and
              crossing file boundaries.

       ESC-u  Undo search highlighting.  Turn off highlighting of strings
              matching the current search pattern.  If highlighting is already
              off because of a previous ESC-u command, turn highlighting back
              on.  Any search command will also turn highlighting back on.
              (Highlighting can also be disabled by toggling the -G option; in
              that case search commands do not turn highlighting back on.)

       ESC-U  Like ESC-u but also clears the saved search pattern.  If the
              status column is enabled via the -J option, this clears all
              search matches marked in the status column.

       &pattern
              Display only lines which match the pattern; lines which do not
              match the pattern are not displayed.  If pattern is empty (if
              you type & immediately followed by ENTER), any filtering is
              turned off, and all lines are displayed.  While filtering is in
              effect, an ampersand is displayed at the beginning of the
              prompt, as a reminder that some lines in the file may be hidden.
              Multiple & commands may be entered, in which case only lines
              which match all of the patterns will be displayed.

              Certain characters are special as in the / command:

              ^N or !
                     Display only lines which do NOT match the pattern.

              ^R     Don't interpret regular expression metacharacters; that
                     is, do a simple textual comparison.

       :e [filename]
              Examine a new file.  If the filename is missing, the "current"
              file (see the :n and :p commands below) from the list of files
              in the command line is re-examined.  A percent sign (%) in the
              filename is replaced by the name of the current file.  A pound
              sign (#) is replaced by the name of the previously examined
              file.  However, two consecutive percent signs are simply
              replaced with a single percent sign.  This allows you to enter a
              filename that contains a percent sign in the name.  Similarly,
              two consecutive pound signs are replaced with a single pound
              sign.  The filename is inserted into the command line list of
              files so that it can be seen by subsequent :n and :p commands.
              If the filename consists of several files, they are all inserted
              into the list of files and the first one is examined.  If the
              filename contains one or more spaces, the entire filename should
              be enclosed in double quotes (also see the -" option).

       ^X^V or E
              Same as :e.  Warning: some systems use ^V as a special
              literalization character.  On such systems, you may not be able
              to use ^V.

       :n     Examine the next file (from the list of files given in the
              command line).  If a number N is specified, the N-th next file
              is examined.

       :p     Examine the previous file in the command line list.  If a number
              N is specified, the N-th previous file is examined.

       :x     Examine the first file in the command line list.  If a number N
              is specified, the N-th file in the list is examined.

       :d     Remove the current file from the list of files.

       t      Go to the next tag, if there were more than one matches for the
              current tag.  See the -t option for more details about tags.

       T      Go to the previous tag, if there were more than one matches for
              the current tag.

       ^O^N or ^On
              Search forward in the file for the N-th next OSC 8 hyperlink.

       ^O^P or ^Op
              Search backward in the file for the N-th previous OSC 8
              hyperlink.

       ^O^L or ^Ol
              Jump to the currently selected OSC 8 hyperlink.

       = or ^G or :f
              Prints some information about the file being viewed, including
              its name and the line number and byte offset of the bottom line
              being displayed.  If possible, it also prints the length of the
              file, the number of lines in the file and the percent of the
              file above the last displayed line.

       -      Followed by one of the command line option letters (see OPTIONS
              below), this will change the setting of that option and print a
              message describing the new setting.  If a ^P (CONTROL-P) is
              entered immediately after the dash, the setting of the option is
              changed but no message is printed.  If the option letter has a
              numeric value (such as -b or -h), or a string value (such as -P
              or -t), a new value may be entered after the option letter.  If
              no new value is entered, a message describing the current
              setting is printed and nothing is changed.

       --     Like the - command, but takes a long option name (see OPTIONS
              below) rather than a single option letter.  You must press ENTER
              or RETURN after typing the option name.  A ^P immediately after
              the second dash suppresses printing of a message describing the
              new setting, as in the - command.

       -+     Followed by one of the command line option letters this will
              reset the option to its default setting and print a message
              describing the new setting.  (The "-+X" command does the same
              thing as "-+X" on the command line.)  This does not work for
              string-valued options.

       --+    Like the -+ command, but takes a long option name rather than a
              single option letter.

       -!     Followed by one of the command line option letters, this will
              reset the option to the "opposite" of its default setting and
              print a message describing the new setting.  This does not work
              for numeric or string-valued options.

       --!    Like the -! command, but takes a long option name rather than a
              single option letter.

       _      (Underscore.)  Followed by one of the command line option
              letters, this will print a message describing the current
              setting of that option.  The setting of the option is not
              changed.

       __     (Double underscore.)  Like the _ (underscore) command, but takes
              a long option name rather than a single option letter.  You must
              press ENTER or RETURN after typing the option name.

       +cmd   Causes the specified cmd to be executed each time a new file is
              examined.  For example, +G causes less to initially display each
              file starting at the end rather than the beginning.

       V      Prints the version number of less being run.

       q or Q or :q or :Q or ZZ
              Exits less.

       The following seven commands may or may not be valid, depending on your
       particular installation.

       v      Invokes an editor to edit the current file being viewed.  The
              editor is taken from the environment variable VISUAL if defined,
              or EDITOR if VISUAL is not defined, or defaults to "vi" if
              neither VISUAL nor EDITOR is defined.  See also the discussion
              of LESSEDIT under the section on PROMPTS below.

       ! shell-command
              Invokes a shell to run the shell-command given.  A percent sign
              (%) in the command is replaced by the name of the current file.
              A pound sign (#) is replaced by the name of the previously
              examined file.  "!!" repeats the last shell command.  "!" with
              no shell command simply invokes a shell.  If a ^P (CONTROL-P) is
              entered immediately after the !, no "done" message is printed
              after the shell command is executed.  On Unix systems, the shell
              is taken from the environment variable SHELL, or defaults to
              "sh".  On MS-DOS, Windows, and OS/2 systems, the shell is the
              normal command processor.

       # shell-command
              Similar to the "!" command, except that the command is expanded
              in the same way as prompt strings.  For example, the name of the
              current file would be given as "%f".

       | <m> shell-command
              <m> represents any mark letter.  Pipes a section of the input
              file to the given shell command.  The section of the file to be
              piped is between the position marked by the letter and the
              current screen.  The entire current screen is included,
              regardless of whether the marked position is before or after the
              current screen.  <m> may also be ^ or $ to indicate beginning or
              end of file respectively.  If <m> is . or newline, the current
              screen is piped.  If a ^P (CONTROL-P) is entered immediately
              after the mark letter, no "done" message is printed after the
              shell command is executed.

       s filename
              Save the input to a file.  This works only if the input is a
              pipe, not an ordinary file.

       ^O^O
              Run a shell command to open the URI in the current OSC 8
              hyperlink, selected by a previous ^O^N or ^O^P command.  To find
              the shell command, the environment variable named
              "LESS_OSC8_xxx" is read, where "xxx" is the scheme from the URI
              (the part before the first colon), or is empty if there is no
              colon in the URI.  The value of the environment variable is then
              expanded in the same way as prompt strings (in particular, any
              instance of "%o" is replaced with the URI) to produce an OSC 8
              "handler" shell command.  The standard output from the handler
              is an "opener" shell command which is then executed to open the
              URI.

              There are two special cases:

                     1.     If the URI begins with "#", the remainder of the
                            URI is taken to be the value of the id parameter
                            in another OSC 8 link in the same file, and ^O^O
                            will simply jump to that link.

                     2.     If the opener begins with the characters ":e"
                            followed by whitespace and a filename, then
                            instead of running the opener as a shell command,
                            the specified filename is opened in the current
                            instance of less.

              In a simple case where the opener accepts the complete URI as a
              command line parameter, the handler may be as simple as

              echo mybrowser '%o'

              In other cases, the URI may need to be modified, so the handler
              may have to do some manipulation of the %o value.

              If the LESS_OSC8_xxx variable is not set, the variable
              LESS_OSC8_ANY is tried.  If neither LESS_OSC8_xxx nor
              LESS_OSC8_ANY is set, links using the "xxx" scheme cannot be
              opened.  However, there are default handlers for the schemes
              "man" (used when LESS_OSC8_man is not set) and "file" (used when
              LESS_OSC8_file is not set), which should work on systems which
              provide the sed(1) command and a shell with syntax compatible
              with the Bourne shell sh(1).  If you use LESS_OSC8_ANY to
              override LESS_OSC8_file, you must set LESS_OSC8_file to "-" to
              indicate that the default value should not be used, and likewise
              for LESS_OSC8_man.

              The URI passed to an OSC8 handler via %o is guaranteed not to
              contain any single quote or double quote characters, but it may
              contain any other shell metacharacters such as semicolons,
              dollar signs, ampersands, etc.  The handler should take care to
              appropriately quote parameters in the opener command, to prevent
              execution of unintended shell commands in the case of opening a
              URI which contains shell metacharacters.  Also, since the
              handler command is expanded like a command prompt, any
              metacharacters interpreted by prompt expansion (such as percent,
              dot, colon, backslash, etc.) must be escaped with a backslash
              (see the PROMPTS section for details).

       ^X     When the "Waiting for data" message is displayed, such as while
              in the F command, pressing ^X will stop less from waiting and
              return to a prompt.  This may cause less to think that the file
              ends at the current position, so it may be necessary to use the
              R or F command to see more data.  The --intr option can be used
              to specify a different character to use instead of ^X.  This
              command works only on systems that support the poll(2) function.
              On systems without poll(2), the interrupt character (usually ^C)
              can be used instead.


OPTIONS

       Command line options are described below.  Most options may be changed
       while less is running, via the "-" command.

       Some options may be given in one of two forms: either a dash followed
       by a single letter, or two dashes followed by a long option name.  A
       long option name may be abbreviated as long as the abbreviation is
       unambiguous.  For example, --quit-at-eof may be abbreviated --quit, but
       not --qui, since both --quit-at-eof and --quiet begin with --qui.  Some
       long option names are in uppercase, such as --QUIT-AT-EOF, as distinct
       from --quit-at-eof.  Such option names need only have their first
       letter capitalized; the remainder of the name may be in either case.
       For example, --Quit-at-eof is equivalent to --QUIT-AT-EOF.

       Options are also taken from the environment variable "LESS".  For
       example, to avoid typing "less -options ..." each time less is invoked,
       you might tell csh:

       setenv LESS "-options"

       or if you use sh:

       LESS="-options"; export LESS

       On MS-DOS and Windows, you don't need the quotes, but you should be
       careful that any percent signs in the options string are not
       interpreted as an environment variable expansion.

       The environment variable is parsed before the command line, so command
       line options override the LESS environment variable.  If an option
       appears in the LESS variable, it can be reset to its default value on
       the command line by beginning the command line option with "-+".

       Some options like -k or -D require a string to follow the option
       letter.  The string for that option is considered to end when a dollar
       sign ($) is found.  For example, you can set two -D options like this:

       LESS="Dnwb$Dsbw"

       If the --use-backslash option appears earlier in the options, then a
       dollar sign or backslash may be included literally in an option string
       by preceding it with a backslash.  If the --use-backslash option is not
       in effect, then backslashes are not treated specially, and there is no
       way to include a dollar sign in the option string.

       -? or --help
              This option displays a summary of the commands accepted by less
              (the same as the h command).  (Depending on how your shell
              interprets the question mark, it may be necessary to quote the
              question mark, thus: "-\?".)

       -a or --search-skip-screen
              By default, forward searches start at the top of the displayed
              screen and backwards searches start at the bottom of the
              displayed screen (except for repeated searches invoked by the n
              or N commands, which start after or before the "target" line
              respectively; see the -j option for more about the target line).
              The -a option causes forward searches to instead start at the
              bottom of the screen and backward searches to start at the top
              of the screen, thus skipping all lines displayed on the screen.

       -A or --SEARCH-SKIP-SCREEN
              Causes all forward searches (not just non-repeated searches) to
              start just after the target line, and all backward searches to
              start just before the target line.  Thus, forward searches will
              skip part of the displayed screen (from the first line up to and
              including the target line).  Similarly backwards searches will
              skip the displayed screen from the last line up to and including
              the target line.  This was the default behavior in less versions
              prior to 441.

       -bn or --buffers=n
              Specifies the amount of buffer space less will use for each
              file, in units of kilobytes (1024 bytes).  By default 64 KB of
              buffer space is used for each file (unless the file is a pipe;
              see the -B option).  The -b option specifies instead that n
              kilobytes of buffer space should be used for each file.  If n is
              -1, buffer space is unlimited; that is, the entire file can be
              read into memory.

       -B or --auto-buffers
              By default, when data is read from a pipe, buffers are allocated
              automatically as needed.  If a large amount of data is read from
              the pipe, this can cause a large amount of memory to be
              allocated.  The -B option disables this automatic allocation of
              buffers for pipes, so that only 64 KB (or the amount of space
              specified by the -b option) is used for the pipe.  Warning: use
              of -B can result in erroneous display, since only the most
              recently viewed part of the piped data is kept in memory; any
              earlier data is lost.  Lost characters are displayed as question
              marks.

       -c or --clear-screen
              Causes full screen repaints to be painted from the top line
              down.  By default, full screen repaints are done by scrolling
              from the bottom of the screen.

       -C or --CLEAR-SCREEN
              Same as -c, for compatibility with older versions of less.

       -d or --dumb
              The -d option suppresses the error message normally displayed if
              the terminal is dumb; that is, lacks some important capability,
              such as the ability to clear the screen or scroll backward.  The
              -d option does not otherwise change the behavior of less on a
              dumb terminal.

       -Dxcolor or --color=xcolor
              Changes the color of different parts of the displayed text.  x
              is a single character which selects the type of text whose color
              is being set:

              B      Binary characters.

              C      Control characters.

              E      Errors and informational messages.

              H      Header lines and columns, set via the --header option.

              M      Mark letters in the status column.

              N      Line numbers enabled via the -N option.

              P      Prompts.

              R      The rscroll character.

              S      Search results.

              W      The highlight enabled via the -w option.

              1-5    The text in a search result which matches the first
                     through fifth parenthesized sub-pattern.  Sub-pattern
                     coloring works only if less is built with one of the
                     regular expression libraries posix, pcre, or pcre2.

              d      Bold text.

              k      Blinking text.

              s      Standout text.

              u      Underlined text.

              The uppercase letters and digits can be used only when the
              --use-color option is enabled.  When text color is specified by
              both an uppercase letter and a lowercase letter, the uppercase
              letter takes precedence.  For example, error messages are
              normally displayed as standout text.  So if both "s" and "E" are
              given a color, the "E" color applies to error messages, and the
              "s" color applies to other standout text.  The lowercase letters
              refer to bold and underline text formed by overstriking with
              backspaces (see the -U option) and to non-content text (such as
              line numbers and prompts), but not to text formatted using ANSI
              escape sequences with the -R option (but see the note below for
              different behavior on Windows and MS-DOS).

              A lowercase letter may be followed by a + to indicate that the
              normal format change and the specified color should both be
              used.  For example, -Dug displays underlined text as green
              without underlining; the green color has replaced the usual
              underline formatting.  But -Du+g displays underlined text as
              both green and in underlined format.

              color is either a 4-bit color string or an 8-bit color string:

              A 4-bit color string is one or two characters, where the first
              character specifies the foreground color and the second
              specifies the background color as follows:

              b      Blue

              c      Cyan

              g      Green

              k      Black

              m      Magenta

              r      Red

              w      White

              y      Yellow

              The corresponding uppercase letter denotes a brighter shade of
              the color.  For example, -DNGk displays line numbers as bright
              green text on a black background, and -DEbR displays error
              messages as blue text on a bright red background.  If either
              character is a "-" or is omitted, the corresponding color is set
              to that of normal text.

              An 8-bit color string is one or two decimal integers separated
              by a dot, where the first integer specifies the foreground color
              and the second specifies the background color.  Each integer is
              a value between 0 and 255 inclusive which selects a "CSI 38;5"
              color value (see
              https://en.wikipedia.org/wiki/ANSI_escape_code#SGR).  If either
              integer is a "-" or is omitted, the corresponding color is set
              to that of normal text.

              A 4-bit or 8-bit color string may be followed by one or more of
              the following characters to set text attributes in addition to
              the color.

              s or ~ Standout (reverse video)

              u or _ Underline

              d or * Bold

              l or & Blinking

              On MS-DOS and Windows, the --color option behaves differently
              from what is described above in these ways:

              o      The bold (d and *) and blinking (l and &) text attributes
                     at the end of a color string are not supported.

              o      Lowercase color selector letters refer to text formatted
                     by ANSI escape sequences with -R, in addition to
                     overstruck and non-content text (but see -Da).

              o      For historical reasons, when a lowercase color selector
                     letter is followed by a numeric color value, the number
                     is not interpreted as an "CSI 38;5" color value as
                     described above, but instead as a 4-bit
                     CHAR_INFO.Attributes value, between 0 and 15 inclusive
                     (see https://learn.microsoft.com/en-
                     us/windows/console/char-info-str).

                     To avoid confusion, it is recommended that the equivalent
                     letters rather than numbers be used after a lowercase
                     color selector on MS-DOS/Windows.

              o      Numeric color values ("CSI 38;5" color) following an
                     uppercase color selector letter are not supported on
                     systems earlier than Windows 10.

              o      Only a limited set of ANSI escape sequences to set color
                     in the content work correctly.  4-bit color sequences
                     work, but "CSI 38;5" color sequences do not.

              o      The -Da option makes the behavior of --color more similar
                     to its behavior on non-MS-DOS/Windows systems by (1)
                     making lowercase color selector letters not affect text
                     formatted with ANSI escape sequences, and (2) allowing
                     "CSI 38;5" color sequences in the content work by passing
                     them to the terminal (only on Windows 10 and later; on
                     earlier Windows systems, such sequences do not work
                     regardless of the setting of -Da).

       -e or --quit-at-eof
              Causes less to automatically exit the second time it reaches
              end-of-file.  By default, the only way to exit less is via the
              "q" command.

       -E or --QUIT-AT-EOF
              Causes less to automatically exit the first time it reaches end-
              of-file.

       -f or --force
              Forces non-regular files to be opened.  (A non-regular file is a
              directory or a device special file.)  Also suppresses the
              warning message when a binary file is opened.  By default, less
              will refuse to open non-regular files.  Note that some operating
              systems will not allow directories to be read, even if -f is
              set.

       -F or --quit-if-one-screen
              Causes less to automatically exit if the entire file can be
              displayed on the first screen.

       -g or --hilite-search
              Normally, less will highlight ALL strings which match the last
              search command.  The -g option changes this behavior to
              highlight only the particular string which was found by the last
              search command.  This can cause less to run somewhat faster than
              the default.

       -G or --HILITE-SEARCH
              The -G option suppresses all highlighting of strings found by
              search commands.

       -hn or --max-back-scroll=n
              Specifies a maximum number of lines to scroll backward.  If it
              is necessary to scroll backward more than n lines, the screen is
              repainted in a forward direction instead.  (If the terminal does
              not have the ability to scroll backward, -h0 is implied.)

       -i or --ignore-case
              Causes searches to ignore case; that is, uppercase and lowercase
              are considered identical.  This option is ignored if any
              uppercase letters appear in the search pattern; in other words,
              if a pattern contains uppercase letters, then that search does
              not ignore case.

       -I or --IGNORE-CASE
              Like -i, but searches ignore case even if the pattern contains
              uppercase letters.

       -jn or --jump-target=n
              Specifies a line on the screen where the "target" line is to be
              positioned.  The target line is the line specified by any
              command to search for a pattern, jump to a line number, jump to
              a file percentage or jump to a tag.  The screen line may be
              specified by a number: the top line on the screen is 1, the next
              is 2, and so on.  The number may be negative to specify a line
              relative to the bottom of the screen: the bottom line on the
              screen is -1, the second to the bottom is -2, and so on.
              Alternately, the screen line may be specified as a fraction of
              the height of the screen, starting with a decimal point: .5 is
              in the middle of the screen, .3 is three tenths down from the
              first line, and so on.  If the line is specified as a fraction,
              the actual line number is recalculated if the terminal window is
              resized.  If the --header option is used and the target line
              specified by -j would be obscured by the header, the target line
              is moved to the first line after the header.  While the --header
              option is active, the -S option is ignored, and lines longer
              than the screen width are truncated.

              If any form of the -j option is used, repeated forward searches
              (invoked with "n" or "N") begin at the line immediately after
              the target line, and repeated backward searches begin at the
              target line, unless changed by -a or -A.  For example, if "-j4"
              is used, the target line is the fourth line on the screen, so
              forward searches begin at the fifth line on the screen.  However
              nonrepeated searches (invoked with "/" or "?") always begin at
              the start or end of the current screen respectively.

       -J or --status-column
              Displays a status column at the left edge of the screen.  The
              character displayed in the status column may be one of:

              >      The line is chopped with the -S option, and the text that
                     is chopped off beyond the right edge of the screen
                     contains a match for the current search.

              <      The line is horizontally shifted, and the text that is
                     shifted beyond the left side of the screen contains a
                     match for the current search.

              =      The line is both chopped and shifted, and there are
                     matches beyond both sides of the screen.

              *      There are matches in the visible part of the line but
                     none to the right or left of it.

              a-z, A-Z
                     The line has been marked with the corresponding letter
                     via the m command.

       -kfilename or --lesskey-file=filename
              Causes less to open and interpret the named file as a lesskey(1)
              binary file.  Multiple -k options may be specified.  If the
              LESSKEY or LESSKEY_SYSTEM environment variable is set, or if a
              lesskey file is found in a standard place (see KEY BINDINGS), it
              is also used as a lesskey file.  Note the warning under
              "--lesskey-content" below.

       --lesskey-src=filename
              Causes less to open and interpret the named file as a lesskey(1)
              source file.  If the LESSKEYIN or LESSKEYIN_SYSTEM environment
              variable is set, or if a lesskey source file is found in a
              standard place (see KEY BINDINGS), it is also used as a lesskey
              source file.  Prior to version 582, the lesskey program needed
              to be run to convert a lesskey source file to a lesskey binary
              file for less to use.  Newer versions of less read the lesskey
              source file directly and ignore the binary file if the source
              file exists.  Note the warning under "--lesskey-content" below.

       --lesskey-content=text
              Causes less to interpret the specified text as the contents of a
              lesskey(1) source file.  In the text, lesskey lines may be
              separated by either newlines as usual, or by semicolons.  A
              literal semicolon may be represented by a backslash followed by
              a semicolon.

              Warning: certain environment variables such as LESS, LESSSECURE,
              LESSCHARSET and others, which are used early in startup, cannot
              be set in a file specified by a command line option (--lesskey,
              --lesskey-src or --lesskey-content).  When using a lesskey file
              to set environment variables, it is safer to use the default
              lesskey file, or to specify the file using the LESSKEYIN or
              LESSKEY_CONTENT environment variables rather than using a
              command line option.

       -K or --quit-on-intr
              Causes less to exit immediately (with status 2) when an
              interrupt character (usually ^C) is typed.  Normally, an
              interrupt character causes less to stop whatever it is doing and
              return to its command prompt.  Note that use of this option
              makes it impossible to return to the command prompt from the "F"
              command.

       -L or --no-lessopen
              Ignore the LESSOPEN environment variable (see the INPUT
              PREPROCESSOR section below).  This option can be set from within
              less, but it will apply only to files opened subsequently, not
              to the file which is currently open.

       -m or --long-prompt
              Causes less to prompt verbosely (like more(1)), with the percent
              into the file.  By default, less prompts with a colon.

       -M or --LONG-PROMPT
              Causes less to prompt even more verbosely than more(1).

       -n or --line-numbers
              Suppresses line numbers.  The default (to use line numbers) may
              cause less to run more slowly in some cases, especially with a
              very large input file.  Suppressing line numbers with the -n
              option will avoid this problem.  Using line numbers means: the
              line number will be displayed in the verbose prompt and in the =
              command, and the v command will pass the current line number to
              the editor (see also the discussion of LESSEDIT in PROMPTS
              below).

       -N or --LINE-NUMBERS
              Causes a line number to be displayed at the beginning of each
              line in the display.

       -ofilename or --log-file=filename
              Causes less to copy its input to the named file as it is being
              viewed.  This applies only when the input file is a pipe, not an
              ordinary file.  If the file already exists, less will ask for
              confirmation before overwriting it.

       -Ofilename or --LOG-FILE=filename
              The -O option is like -o, but it will overwrite an existing file
              without asking for confirmation.

              If no log file has been specified, the -o and -O options can be
              used from within less to specify a log file.  Without a file
              name, they will simply report the name of the log file.  The "s"
              command is equivalent to specifying -o from within less.

       -ppattern or --pattern=pattern
              The -p option on the command line is equivalent to specifying
              +/pattern; that is, it tells less to start at the first
              occurrence of pattern in the file.

       -Pprompt or --prompt=prompt
              Provides a way to tailor the three prompt styles to your own
              preference.  This option would normally be put in the LESS
              environment variable, rather than being typed in with each less
              command.  Such an option must either be the last option in the
              LESS variable, or be terminated by a dollar sign.
               -Ps followed by a string changes the default (short) prompt to
              that string.
               -Pm changes the medium (-m) prompt.
               -PM changes the long (-M) prompt.
               -Ph changes the prompt for the help screen.
               -P= changes the message printed by the = command.
               -Pw changes the message printed while waiting for data (in the
              "F" command).

              All prompt strings consist of a sequence of letters and special
              escape sequences.  See the section on PROMPTS for more details.

       -q or --quiet or --silent
              Causes moderately "quiet" operation: the terminal bell is not
              rung if an attempt is made to scroll past the end of the file or
              before the beginning of the file.  If the terminal has a "visual
              bell", it is used instead.  The bell will be rung on certain
              other errors, such as typing an invalid character.  The default
              is to ring the terminal bell in all such cases.

       -Q or --QUIET or --SILENT
              Causes totally "quiet" operation: the terminal bell is never
              rung.  If the terminal has a "visual bell", it is used in all
              cases where the terminal bell would have been rung.

       -r or --raw-control-chars
              Causes "raw" control characters to be displayed.  The default is
              to display control characters using the caret notation; for
              example, a control-A (octal 001) is displayed as "^A" (with some
              exceptions as described under the -U option).  Warning: when the
              -r option is used, less cannot keep track of the actual
              appearance of the screen (since this depends on how the screen
              responds to each type of control character).  Thus, various
              display problems may result, such as long lines being split in
              the wrong place.

              USE OF THE -r OPTION IS NOT RECOMMENDED.

       -R or --RAW-CONTROL-CHARS
              Like -r, but only ANSI "color" escape sequences and OSC 8
              hyperlink sequences are output in "raw" form.  Unlike -r, the
              screen appearance is maintained correctly, provided that there
              are no escape sequences in the file other than these types of
              escape sequences.  Color escape sequences are only supported
              when the color is changed within one line, not across lines.  In
              other words, the beginning of each line is assumed to be normal
              (non-colored), regardless of any escape sequences in previous
              lines.  For the purpose of keeping track of screen appearance,
              these escape sequences are assumed to not move the cursor.

              OSC 8 hyperlinks are sequences of the form:

                   ESC ] 8 ; ... \7

              The terminating sequence may be either a BEL character (\7) or
              the two-character sequence "ESC \".

              ANSI color escape sequences are sequences of the form:

                   ESC [ ... m

              where the "..." is zero or more color specification characters.
              You can make less think that characters other than "m" can end
              ANSI color escape sequences by setting the environment variable
              LESSANSIENDCHARS to the list of characters which can end a color
              escape sequence.  And you can make less think that characters
              other than the standard ones may appear between the ESC and the
              m by setting the environment variable LESSANSIMIDCHARS to the
              list of characters which can appear.

       -s or --squeeze-blank-lines
              Causes consecutive blank lines to be squeezed into a single
              blank line.  This is useful when viewing nroff output.

       -S or --chop-long-lines
              Causes lines longer than the screen width to be chopped
              (truncated) rather than wrapped.  That is, the portion of a long
              line that does not fit in the screen width is not displayed
              until you press RIGHT-ARROW.  The default is to wrap long lines;
              that is, display the remainder on the next line.  See also the
              --wordwrap option.

       -ttag or --tag=tag
              The -t option, followed immediately by a TAG, will edit the file
              containing that tag.  For this to work, tag information must be
              available; for example, there may be a file in the current
              directory called "tags", which was previously built by ctags(1)
              or an equivalent command.  If the environment variable
              LESSGLOBALTAGS is set, it is taken to be the name of a command
              compatible with global(1), and that command is executed to find
              the tag.  (See http://www.gnu.org/software/global/global.html).
              The -t option may also be specified from within less (using the
              - command) as a way of examining a new file.  The command ":t"
              is equivalent to specifying -t from within less.

       -Ttagsfile or --tag-file=tagsfile
              Specifies a tags file to be used instead of "tags".

       -u or --underline-special
              Causes backspaces and carriage returns to be treated as
              printable characters; that is, they are sent to the terminal
              when they appear in the input.

       -U or --UNDERLINE-SPECIAL
              Causes backspaces, tabs, carriage returns and "formatting
              characters" (as defined by Unicode) to be treated as control
              characters; that is, they are handled as specified by the -r
              option.

              By default, if neither -u nor -U is given, backspaces which
              appear adjacent to an underscore character are treated
              specially: the underlined text is displayed using the terminal's
              hardware underlining capability.  Also, backspaces which appear
              between two identical characters are treated specially: the
              overstruck text is printed using the terminal's hardware
              boldface capability.  Other backspaces are deleted, along with
              the preceding character.  Carriage returns immediately followed
              by a newline are deleted.  Other carriage returns are handled as
              specified by the -r option.  Unicode formatting characters, such
              as the Byte Order Mark, are sent to the terminal.  Text which is
              overstruck or underlined can be searched for if neither -u nor
              -U is in effect.

              See also the --proc-backspace, --proc-tab, and --proc-return
              options.

       -V or --version
              Displays the version number of less.

       -w or --hilite-unread
              Temporarily highlights the first "new" line after a forward
              movement of a full page.  The first "new" line is the line
              immediately following the line previously at the bottom of the
              screen.  Also highlights the target line after a g or p command.
              The highlight is removed at the next command which causes
              movement.  If the --status-line option is in effect, the entire
              line (the width of the screen) is highlighted.  Otherwise, only
              the text in the line is highlighted, unless the -J option is in
              effect, in which case only the status column is highlighted.

       -W or --HILITE-UNREAD
              Like -w, but temporarily highlights the first new line after any
              forward movement command larger than one line.

       -xn,... or --tabs=n,...
              Sets tab stops.  If only one n is specified, tab stops are set
              at multiples of n.  If multiple values separated by commas are
              specified, tab stops are set at those positions, and then
              continue with the same spacing as the last two.  For example,
              "-x9,17" will set tabs at positions 9, 17, 25, 33, etc.  The
              default for n is 8.

       -X or --no-init
              Disables sending the termcap initialization and deinitialization
              strings to the terminal.  This is sometimes desirable if the
              deinitialization string does something unnecessary, like
              clearing the screen.

       -yn or --max-forw-scroll=n
              Specifies a maximum number of lines to scroll forward.  If it is
              necessary to scroll forward more than n lines, the screen is
              repainted instead.  The -c or -C option may be used to repaint
              from the top of the screen if desired.  By default, any forward
              movement causes scrolling.

       -zn or --window=n or -n
              Changes the default scrolling window size to n lines.  The
              default is one screenful.  The z and w commands can also be used
              to change the window size.  The "z" may be omitted for
              compatibility with some versions of more(1).  If the number n is
              negative, it indicates n lines less than the current screen
              size.  For example, if the screen is 24 lines, -z-4 sets the
              scrolling window to 20 lines.  If the screen is resized to 40
              lines, the scrolling window automatically changes to 36 lines.

       -"cc or --quotes=cc
              Changes the filename quoting character.  This may be necessary
              if you are trying to name a file which contains both spaces and
              quote characters.  Followed by a single character, this changes
              the quote character to that character.  Filenames containing a
              space should then be surrounded by that character rather than by
              double quotes.  Followed by two characters, changes the open
              quote to the first character, and the close quote to the second
              character.  Filenames containing a space should then be preceded
              by the open quote character and followed by the close quote
              character.  Note that even after the quote characters are
              changed, this option remains -" (a dash followed by a double
              quote).

       -~ or --tilde
              Normally lines after end of file are displayed as a single tilde
              (~).  This option causes lines after end of file to be displayed
              as blank lines.

       -# or --shift
              Specifies the default number of positions to scroll horizontally
              in the RIGHTARROW and LEFTARROW commands.  If the number
              specified is zero, it sets the default number of positions to
              one half of the screen width.  Alternately, the number may be
              specified as a fraction of the width of the screen, starting
              with a decimal point: .5 is half of the screen width, .3 is
              three tenths of the screen width, and so on.  If the number is
              specified as a fraction, the actual number of scroll positions
              is recalculated if the terminal window is resized.

       --exit-follow-on-close
              When using the "F" command on a pipe, less will automatically
              stop waiting for more data when the input side of the pipe is
              closed.

       --file-size
              If --file-size is specified, less will determine the size of the
              file immediately after opening the file.  Then the "=" command
              will display the number of lines in the file.  Normally this is
              not done, because it can be slow if the input file is non-
              seekable (such as a pipe) and is large.

       --follow-name
              Normally, if the input file is renamed while an F command is
              executing, less will continue to display the contents of the
              original file despite its name change.  If --follow-name is
              specified, during an F command less will periodically attempt to
              reopen the file by name.  If the reopen succeeds and the file is
              a different file from the original (which means that a new file
              has been created with the same name as the original (now
              renamed) file), less will display the contents of that new file.

       --header=L,C,N
              Sets the number of header lines and columns displayed on the
              screen.  The number of header lines is set to L.  If L is 0,
              header lines are disabled.  If L is empty or missing, the number
              of header lines is unchanged.  The number of header columns is
              set to C.  If C is 0, header columns are disabled.  If C is
              empty or missing, the number of header columns is unchanged.
              The first header line is set to line number N in the file.  If N
              is empty or missing, it is taken to be the number of the line
              currently displayed in the first line of the screen (if the
              --header command has been issued from within less), or 1 (if the
              --header option has been given on the command line).  The
              special form "--header=-" disables header lines and header
              columns, and is equivalent to "--header=0,0".

              When L is nonzero, the first L lines at the top of the screen
              are replaced with the L lines of the file beginning at line N,
              regardless of what part of the file is being viewed.  When
              header lines are displayed, any file contents before the header
              line cannot be viewed.  When C is nonzero, the first C
              characters displayed at the beginning of each line are replaced
              with the first C characters of the line, even if the rest of the
              line is scrolled horizontally.

       --incsearch
              Subsequent search commands will be "incremental"; that is, less
              will advance to the next line containing the search pattern as
              each character of the pattern is typed in.

       --intr=c
              Use the character c instead of ^X to interrupt a read when the
              "Waiting for data" message is displayed.  c must be an ASCII
              character; that is, one with a value between 1 and 127
              inclusive.  A caret followed by a single character can be used
              to specify a control character.

       --line-num-width=n
              Sets the minimum width of the line number field when the -N
              option is in effect to n characters.  The default is 7.

       --match-shift=n
              When -S is in effect, if a search match is not visible because
              it is shifted to the left or right of the currently visible
              screen, the text will horizontally shift to ensure that the
              search match is visible.  This option selects the column in
              which the first character of the search match will be placed
              after the shift.  In other words, there will be n characters
              visible to the left of the search match.

              Alternately, the number may be specified as a fraction of the
              width of the screen, starting with a decimal point: .5 is half
              of the screen width, .3 is three tenths of the screen width, and
              so on.  If the number is specified as a fraction, the actual
              number of scroll positions is recalculated if the terminal
              window is resized.

       --modelines=n
              Before displaying a file, less will read the first n lines to
              try to find a vim-compatible modeline.  If n is zero, less does
              not try to find modelines.  By using a modeline, the file itself
              can specify the tab stops that should be used when viewing it.

              A modeline contains, anywhere in the line, a program name ("vi",
              "vim", "ex", or "less"), followed by a colon, possibly followed
              by the word "set", and finally followed by zero or more option
              settings.  If the word "set" is used, option settings are
              separated by spaces, and end at the first colon.  If the word
              "set" is not used, option settings may be separated by either
              spaces or colons.  The word "set" is required if the program
              name is "less" but optional if any of the other three names are
              used.  If any option setting is of the form "tabstop=n" or
              "ts=n", then tab stops are automatically set as if --tabs=n had
              been given.  See the --tabs description for acceptable values of
              n.

       --mouse
              Enables mouse input: scrolling the mouse wheel down moves
              forward in the file, scrolling the mouse wheel up moves
              backwards in the file, left-click sets the "#" mark to the line
              where the mouse is clicked, and right-click (or any other)
              returns to the "#" mark position.  If a left-click is performed
              with the mouse cursor on an OSC 8 hyperlink, the hyperlink is
              selected as if by the ^O^N command.  If a left-click is
              performed with the mouse cursor on an OSC 8 hyperlink which is
              already selected, the hyperlink is opened as if by the ^O^O
              command.  The number of lines to scroll when the wheel is moved
              can be set by the --wheel-lines option.  Mouse input works only
              on terminals which support X11 mouse reporting, and on the
              Windows version of less.

       --MOUSE
              Like --mouse, except the direction scrolled on mouse wheel
              movement is reversed.

       --no-keypad
              Disables sending the keypad initialization and deinitialization
              strings to the terminal.  This is sometimes useful if the keypad
              strings make the numeric keypad behave in an undesirable manner.

       --no-histdups
              This option changes the behavior so that if a search string or
              file name is typed in, and the same string is already in the
              history list, the existing copy is removed from the history list
              before the new one is added.  Thus, a given string will appear
              only once in the history list.  Normally, a string may appear
              multiple times.

       --no-number-headers
              Header lines (defined via the --header option) are not assigned
              line numbers.  Line number 1 is assigned to the first line after
              any header lines.

       --no-search-header-lines
              Searches do not include header lines, but still include header
              columns.

       --no-search-header-columns
              Searches do not include header columns, but still include header
              lines.

       --no-search-headers
              Searches do not include header lines or header columns.

       --no-vbell
              Disables the terminal's visual bell.

       --proc-backspace
              If set, backspaces are handled as if neither the -u option nor
              the -U option were set.  That is, a backspace adjacent to an
              underscore causes text to be displayed in underline mode, and a
              backspace between identical characters cause text to be
              displayed in boldface mode.  This option overrides the -u and -U
              options, so that display of backspaces can be controlled
              separate from tabs and carriage returns.  If not set, backspace
              display is controlled by the -u and -U options.

       --PROC-BACKSPACE
              If set, backspaces are handled as if the -U option were set;
              that is backspaces are treated as control characters.

       --proc-return
              If set, carriage returns are handled as if neither the -u option
              nor the -U option were set.  That is, a carriage return
              immediately before a newline is deleted.  This option overrides
              the -u and -U options, so that display of carriage returns can
              be controlled separate from that of backspaces and tabs.  If not
              set, carriage return display is controlled by the -u and -U
              options.

       --PROC-RETURN
              If set, carriage returns are handled as if the -U option were
              set; that is carriage returns are treated as control characters.

       --proc-tab
              If set, tabs are handled as if the -U option were not set.  That
              is, tabs are expanded to spaces.  This option overrides the -U
              option, so that display of tabs can be controlled separate from
              that of backspaces and carriage returns.  If not set, tab
              display is controlled by the -U options.

       --PROC-TAB
              If set, tabs are handled as if the -U option were set; that is
              tabs are treated as control characters.

       --redraw-on-quit
              When quitting, after sending the terminal deinitialization
              string, redraws the entire last screen.  On terminals whose
              terminal deinitialization string causes the terminal to switch
              from an alternate screen, this makes the last screenful of the
              current file remain visible after less has quit.

       --rscroll=c
              This option changes the character used to mark truncated lines.
              It may begin with a two-character attribute indicator like
              LESSBINFMT does.  If there is no attribute indicator, standout
              is used.  If set to "-", truncated lines are not marked.

       --save-marks
              Save marks in the history file, so marks are retained across
              different invocations of less.

       --search-options=...
              Sets default search modifiers.  The value is a string of one or
              more of the characters E, F, K, N, R or W.  Setting any of these
              has the same effect as typing that control character at the
              beginning of every search pattern.  For example, setting
              --search-options=W is the same as typing ^W at the beginning of
              every pattern.  The value may also contain a digit between 1 and
              5, which has the same effect as typing ^S followed by that digit
              at the beginning of every search pattern.  The value "-"
              disables all default search modifiers.

       --show-preproc-errors
              If a preprocessor produces data, then exits with a non-zero exit
              code, less will display a warning.

       --status-col-width=n
              Sets the width of the status column when the -J option is in
              effect.  The default is 2 characters.

       --status-line
              If a line is marked, the entire line (rather than just the
              status column) is highlighted.  Also lines highlighted due to
              the -w option will have the entire line highlighted.  If --use-
              color is set, the line is colored rather than highlighted.

       --use-backslash
              This option changes the interpretations of options which follow
              this one.  After the --use-backslash option, any backslash in an
              option string is removed and the following character is taken
              literally.  This allows a dollar sign to be included in option
              strings.

       --use-color
              Enables colored text in various places.  The -D option can be
              used to change the colors.  Colored text works only if the
              terminal supports ANSI color escape sequences (as defined in
              https://www.ecma-international.org/publications-and-
              standards/standards/ecma-48).

       --wheel-lines=n
              Set the number of lines to scroll when the mouse wheel is
              scrolled and the --mouse or --MOUSE option is in effect.  The
              default is 1 line.

       --wordwrap
              When the -S option is not in use, wrap each line at a space or
              tab if possible, so that a word is not split between two lines.
              The default is to wrap at any character.

       --     A command line argument of "--" marks the end of option
              arguments.  Any arguments following this are interpreted as
              filenames.  This can be useful when viewing a file whose name
              begins with a "-" or "+".

       +      If a command line option begins with +, the remainder of that
              option is taken to be an initial command to less.  For example,
              +G tells less to start at the end of the file rather than the
              beginning, and +/xyz tells it to start at the first occurrence
              of "xyz" in the file.  As a special case, +<number> acts like
              +<number>g; that is, it starts the display at the specified line
              number (however, see the caveat under the "g" command above).
              If the option starts with ++, the initial command applies to
              every file being viewed, not just the first one.  The + command
              described previously may also be used to set (or change) an
              initial command for every file.


LINE EDITING

       When entering a command line at the bottom of the screen (for example,
       a filename for the :e command, or the pattern for a search command),
       certain keys can be used to manipulate the command line.  Most commands
       have an alternate form in [ brackets ] which can be used if a key does
       not exist on a particular keyboard.  (Note that the forms beginning
       with ESC do not work in some MS-DOS and Windows systems because ESC is
       the line erase character.)  Any of these special keys may be entered
       literally by preceding it with the "literal" character, either ^V or
       ^A.  A backslash itself may also be entered literally by entering two
       backslashes.

       LEFTARROW [ ESC-h ]
              Move the cursor one space to the left.

       RIGHTARROW [ ESC-l ]
              Move the cursor one space to the right.

       ^LEFTARROW [ ESC-b or ESC-LEFTARROW ]
              (That is, CONTROL and LEFTARROW simultaneously.)  Move the
              cursor one word to the left.

       ^RIGHTARROW [ ESC-w or ESC-RIGHTARROW ]
              (That is, CONTROL and RIGHTARROW simultaneously.)  Move the
              cursor one word to the right.

       HOME [ ESC-0 ]
              Move the cursor to the beginning of the line.

       END [ ESC-$ ]
              Move the cursor to the end of the line.

       BACKSPACE
              Delete the character to the left of the cursor, or cancel the
              command if the command line is empty.

       DELETE or [ ESC-x ]
              Delete the character under the cursor.

       ^BACKSPACE [ ESC-BACKSPACE ]
              (That is, CONTROL and BACKSPACE simultaneously.)  Delete the
              word to the left of the cursor.

       ^DELETE [ ESC-X or ESC-DELETE ]
              (That is, CONTROL and DELETE simultaneously.)  Delete the word
              under the cursor.

       UPARROW [ ESC-k ]
              Retrieve the previous command line.  If you first enter some
              text and then press UPARROW, it will retrieve the previous
              command which begins with that text.

       DOWNARROW [ ESC-j ]
              Retrieve the next command line.  If you first enter some text
              and then press DOWNARROW, it will retrieve the next command
              which begins with that text.

       TAB    Complete the partial filename to the left of the cursor.  If it
              matches more than one filename, the first match is entered into
              the command line.  Repeated TABs will cycle thru the other
              matching filenames.  If the completed filename is a directory, a
              "/" is appended to the filename.  (On MS-DOS and Windows
              systems, a "\" is appended.)  The environment variable
              LESSSEPARATOR can be used to specify a different character to
              append to a directory name.

       BACKTAB [ ESC-TAB ]
              Like, TAB, but cycles in the reverse direction thru the matching
              filenames.

       ^L     Complete the partial filename to the left of the cursor.  If it
              matches more than one filename, all matches are entered into the
              command line (if they fit).

       ^U (Unix and OS/2) or ESC (MS-DOS and Windows)
              Delete the entire command line, or cancel the command if the
              command line is empty.  If you have changed your line-kill
              character in Unix to something other than ^U, that character is
              used instead of ^U.

       ^G     Delete the entire command line and return to the main prompt.


KEY BINDINGS

       You may define your own less commands by creating a lesskey source
       file.  This file specifies a set of command keys and an action
       associated with each key.  You may also change the line-editing keys
       (see LINE EDITING), and set environment variables used by less.  See
       the lesskey(1) manual page for details about the file format.

       If the environment variable LESSKEYIN is set, less uses that as the
       name of the lesskey source file.  Otherwise, less looks in a standard
       place for the lesskey source file: On Unix systems, less looks for a
       lesskey file called "$XDG_CONFIG_HOME/lesskey" or
       "$HOME/.config/lesskey" or "$HOME/.lesskey".  On MS-DOS and Windows
       systems, less looks for a lesskey file called "$HOME/_lesskey", and if
       it is not found there, then looks for a lesskey file called "_lesskey"
       in any directory specified in the PATH environment variable.  On OS/2
       systems, less looks for a lesskey file called "$HOME/lesskey.ini", and
       if it is not found, then looks for a lesskey file called "lesskey.ini"
       in any directory specified in the INIT environment variable, and if it
       not found there, then looks for a lesskey file called "lesskey.ini" in
       any directory specified in the PATH environment variable.

       A system-wide lesskey source 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
       LESSKEYIN_SYSTEM is set, less uses that as the name of the system-wide
       lesskey file.  Otherwise, less looks in a standard place for the
       system-wide lesskey file: On Unix systems, the system-wide lesskey file
       is /usr/local/etc/syslesskey.  (However, if less was built with a
       different sysconf directory than /usr/local/etc, that directory is
       where the sysless file is found.)  On MS-DOS and Windows systems, the
       system-wide lesskey file is c:\_syslesskey.  On OS/2 systems, the
       system-wide lesskey file is c:\syslesskey.ini.

       Previous versions of less (before v582) used lesskey files with a
       binary format, produced by the lesskey program. It is no longer
       necessary to use the lesskey program.


INPUT PREPROCESSOR

       You may define an "input preprocessor" for less.  Before less opens a
       file, it first gives your input preprocessor a chance to modify the way
       the contents of the file are displayed.  An input preprocessor is
       simply an executable program (or shell script), which writes the
       contents of the file to a different file, called the replacement file.
       The contents of the replacement file are then displayed in place of the
       contents of the original file.  However, it will appear to the user as
       if the original file is opened; that is, less will display the original
       filename as the name of the current file.

       An input preprocessor receives one command line argument, the original
       filename, as entered by the user.  It should create the replacement
       file, and when finished, print the name of the replacement file to its
       standard output.  If the input preprocessor does not output a
       replacement filename, less uses the original file, as normal.  The
       input preprocessor is not called when viewing standard input.  To set
       up an input preprocessor, set the LESSOPEN environment variable to a
       command line which will invoke your input preprocessor.  This command
       line should include one occurrence of the string "%s", which will be
       replaced by the filename when the input preprocessor command is
       invoked.

       When less closes a file opened in such a way, it will call another
       program, called the input postprocessor, which may perform any desired
       clean-up action (such as deleting the replacement file created by
       LESSOPEN).  This program receives two command line arguments, the
       original filename as entered by the user, and the name of the
       replacement file.  To set up an input postprocessor, set the LESSCLOSE
       environment variable to a command line which will invoke your input
       postprocessor.  It may include two occurrences of the string "%s"; the
       first is replaced with the original name of the file and the second
       with the name of the replacement file, which was output by LESSOPEN.

       For example, on many Unix systems, these two scripts will allow you to
       keep files in compressed format, but still let less view them directly:

       lessopen.sh:
            #! /bin/sh
            case "$1" in
            *.Z) TEMPFILE=$(mktemp)
                 uncompress -c $1  >$TEMPFILE  2>/dev/null
                 if [ -s $TEMPFILE ]; then
                      echo $TEMPFILE
                 else
                      rm -f $TEMPFILE
                 fi
                 ;;
            esac

       lessclose.sh:
            #! /bin/sh
            rm $2

       To use these scripts, put them both where they can be executed and set
       LESSOPEN="lessopen.sh %s", and LESSCLOSE="lessclose.sh %s %s".  More
       complex LESSOPEN and LESSCLOSE scripts may be written to accept other
       types of compressed files, and so on.

       It is also possible to set up an input preprocessor to pipe the file
       data directly to less, rather than putting the data into a replacement
       file.  This avoids the need to decompress the entire file before
       starting to view it.  An input preprocessor that works this way is
       called an input pipe.  An input pipe, instead of writing the name of a
       replacement file on its standard output, writes the entire contents of
       the replacement file on its standard output.  If the input pipe does
       not write any characters on its standard output, then there is no
       replacement file and less uses the original file, as normal.  To use an
       input pipe, make the first character in the LESSOPEN environment
       variable a vertical bar (|) to signify that the input preprocessor is
       an input pipe.  As with non-pipe input preprocessors, the command
       string must contain one occurrence of %s, which is replaced with the
       filename of the input file.

       For example, on many Unix systems, this script will work like the
       previous example scripts:

       lesspipe.sh:
            #! /bin/sh
            case "$1" in
            *.Z) uncompress -c $1  2>/dev/null
                 ;;
            *)   exit 1
                 ;;
            esac
            exit $?

       To use this script, put it where it can be executed and set
       LESSOPEN="|lesspipe.sh %s".

       Note that a preprocessor cannot output an empty file, since that is
       interpreted as meaning there is no replacement, and the original file
       is used.  To avoid this, if LESSOPEN starts with two vertical bars, the
       exit status of the script determines the behavior when the output is
       empty.  If the output is empty and the exit status is zero, the empty
       output is considered to be replacement text.  If the output is empty
       and the exit status is nonzero, the original file is used.  For
       compatibility with previous versions of less, if LESSOPEN starts with
       only one vertical bar, the exit status of the preprocessor is ignored.

       When an input pipe is used, a LESSCLOSE postprocessor can be used, but
       it is usually not necessary since there is no replacement file to clean
       up.  In this case, the replacement file name passed to the LESSCLOSE
       postprocessor is "-".

       For compatibility with previous versions of less, the input
       preprocessor or pipe is not used if less is viewing standard input.
       However, if the first character of LESSOPEN is a dash (-), the input
       preprocessor is used on standard input as well as other files.  In this
       case, the dash is not considered to be part of the preprocessor
       command.  If standard input is being viewed, the input preprocessor is
       passed a file name consisting of a single dash.  Similarly, if the
       first two characters of LESSOPEN are vertical bar and dash (|-) or two
       vertical bars and a dash (||-), the input pipe is used on standard
       input as well as other files.  Again, in this case the dash is not
       considered to be part of the input pipe command.


NATIONAL CHARACTER SETS

       There are three types of characters in the input file:

       normal characters
              can be displayed directly to the screen.

       control characters
              should not be displayed directly, but are expected to be found
              in ordinary text files (such as backspace and tab).

       binary characters
              should not be displayed directly and are not expected to be
              found in text files.

       A "character set" is simply a description of which characters are to be
       considered normal, control, and binary.  The LESSCHARSET environment
       variable may be used to select a character set.  Possible values for
       LESSCHARSET are:

       ascii  BS, TAB, NL, CR, and formfeed are control characters, all chars
              with values between 32 and 126 are normal, and all others are
              binary.

       iso8859
              Selects an ISO 8859 character set.  This is the same as ASCII,
              except characters between 160 and 255 are treated as normal
              characters.

       latin1 Same as iso8859.

       latin9 Same as iso8859.

       dos    Selects a character set appropriate for MS-DOS.

       ebcdic Selects an EBCDIC character set.

       IBM-1047
              Selects an EBCDIC character set used by OS/390 Unix Services.
              This is the EBCDIC analogue of latin1.  You get similar results
              by setting either LESSCHARSET=IBM-1047 or LC_CTYPE=en_US in your
              environment.

       koi8-r Selects a Russian character set.

       next   Selects a character set appropriate for NeXT computers.

       utf-8  Selects the UTF-8 encoding of the ISO 10646 character set.
              UTF-8 is special in that it supports multi-byte characters in
              the input file.  It is the only character set that supports
              multi-byte characters.

       windows
              Selects a character set appropriate for Microsoft Windows (cp
              1252).

       In rare cases, it may be desired to tailor less to use a character set
       other than the ones definable by LESSCHARSET.  In this case, the
       environment variable LESSCHARDEF can be used to define a character set.
       It should be set to a string where each character in the string
       represents one character in the character set.  The character "." is
       used for a normal character, "c" for control, and "b" for binary.  A
       decimal number may be used for repetition.  For example, "bccc4b."
       would mean character 0 is binary, 1, 2 and 3 are control, 4, 5, 6 and 7
       are binary, and 8 is normal.  All characters after the last are taken
       to be the same as the last, so characters 9 through 255 would be
       normal.  (This is an example, and does not necessarily represent any
       real character set.)

       This table shows the value of LESSCHARDEF which is equivalent to each
       of the possible values for LESSCHARSET:

            ascii      8bcccbcc18b95.b
            dos        8bcccbcc12bc5b95.b.
            ebcdic     5bc6bcc7bcc41b.9b7.9b5.b..8b6.10b6.b9.7b
                       9.8b8.17b3.3b9.7b9.8b8.6b10.b.b.b.
            IBM-1047   4cbcbc3b9cbccbccbb4c6bcc5b3cbbc4bc4bccbc
                       191.b
            iso8859    8bcccbcc18b95.33b.
            koi8-r     8bcccbcc18b95.b128.
            latin1     8bcccbcc18b95.33b.
            next       8bcccbcc18b95.bb125.bb

       If neither LESSCHARSET nor LESSCHARDEF is set, but any of the strings
       "UTF-8", "UTF8", "utf-8" or "utf8" is found in the LC_ALL, LC_CTYPE or
       LANG environment variables, then the default character set is utf-8.

       If that string is not found, but your system supports the setlocale
       interface, less will use setlocale to determine the character set.
       setlocale is controlled by setting the LANG or LC_CTYPE environment
       variables.

       Finally, if the setlocale interface is also not available, the default
       character set is utf-8.

       Control and binary characters are displayed in standout (reverse
       video).  Each such character is displayed in caret notation if possible
       (e.g. ^A for control-A).  Caret notation is used only if inverting the
       0100 bit results in a normal printable character.  Otherwise, the
       character is displayed as a hex number in angle brackets.  This format
       can be changed by setting the LESSBINFMT environment variable.
       LESSBINFMT may begin with a "*" and one character to select the display
       attribute: "*k" is blinking, "*d" is bold, "*u" is underlined, "*s" is
       standout, and "*n" is normal.  If LESSBINFMT does not begin with a "*",
       normal attribute is assumed.  The remainder of LESSBINFMT is a string
       which may include one printf-style escape sequence (a % followed by x,
       X, o, d, etc.).  For example, if LESSBINFMT is "*u[%x]", binary
       characters are displayed in underlined hexadecimal surrounded by
       brackets.  The default if no LESSBINFMT is specified is "*s<%02X>".
       Warning: the result of expanding the character via LESSBINFMT must be
       less than 31 characters.

       When the character set is utf-8, the LESSUTFBINFMT environment variable
       acts similarly to LESSBINFMT but it applies to Unicode code points that
       were successfully decoded but are unsuitable for display (e.g.,
       unassigned code points).  Its default value is "<U+%04lX>".  Note that
       LESSUTFBINFMT and LESSBINFMT share their display attribute setting
       ("*x") so specifying one will affect both; LESSUTFBINFMT is read after
       LESSBINFMT so its setting, if any, will have priority.  Problematic
       octets in a UTF-8 file (octets of a truncated sequence, octets of a
       complete but non-shortest form sequence, invalid octets, and stray
       trailing octets) are displayed individually using LESSBINFMT so as to
       facilitate diagnostic of how the UTF-8 file is ill-formed.

       When the character set is utf-8, in rare cases it may be desirable to
       override the Unicode definition of the type of certain characters.  For
       example, characters in a Private Use Area are normally treated as
       control characters, but if you are using a custom font with printable
       characters in that range, it may be desirable to tell less to treat
       such characters as printable.  This can be done by setting the
       LESSUTFCHARDEF environment variable to a comma-separated list of
       character type definitions.  Each character type definition consists of
       either one hexadecimal codepoint or a pair of codepoints separated by a
       dash, followed by a colon and a type character.  Each hexadecimal
       codepoint may optionally be preceded by a "U" or "U+".  If a pair of
       codepoints is given, the type is set for all characters inclusively
       between the two values.  If there are multiple comma-separated
       codepoint values, they must be in ascending numerical order.  The type
       character may be one of:

              p      A normal printable character.

              w      A wide (2-space) printable character.

              b      A binary (non-printable) character.

              c      A composing (zero width) character.

       For example, setting LESSUTFCHARDEF to

            E000-F8FF:p,F0000-FFFFD:p,100000-10FFFD:p

       would make all Private Use Area characters be treated as printable.


PROMPTS

       The -P option allows you to tailor the prompt to your preference.  The
       string given to the -P option replaces the specified prompt string.
       Certain characters in the string are interpreted specially.  The prompt
       mechanism is rather complicated to provide flexibility, but the
       ordinary user need not understand the details of constructing
       personalized prompt strings.

       A percent sign followed by a single character is expanded according to
       what the following character is.  (References to the input file size
       below refer to the preprocessed size, if an input preprocessor is being
       used.)

       %bX    Replaced by the byte offset into the current input file.  The b
              is followed by a single character (shown as X above) which
              specifies the line whose byte offset is to be used.  If the
              character is a "t", the byte offset of the top line in the
              display is used, an "m" means use the middle line, a "b" means
              use the bottom line, a "B" means use the line just after the
              bottom line, and a "j" means use the "target" line, as specified
              by the -j option.

       %B     Replaced by the size of the current input file.

       %c     Replaced by the column number of the text appearing in the first
              column of the screen.

       %dX    Replaced by the page number of a line in the input file.  The
              line to be used is determined by the X, as with the %b option.

       %D     Replaced by the number of pages in the input file, or
              equivalently, the page number of the last line in the input
              file.

       %E     Replaced by the name of the editor (from the VISUAL environment
              variable, or the EDITOR environment variable if VISUAL is not
              defined).  See the discussion of the LESSEDIT feature below.

       %f     Replaced by the name of the current input file.

       %F     Replaced by the last component of the name of the current input
              file.

       %g     Replaced by the shell-escaped name of the current input file.
              This is useful when the expanded string will be used in a shell
              command, such as in LESSEDIT.

       %i     Replaced by the index of the current file in the list of input
              files.

       %lX    Replaced by the line number of a line in the input file.  The
              line to be used is determined by the X, as with the %b option.

       %L     Replaced by the line number of the last line in the input file.

       %m     Replaced by the total number of input files.

       %o     Replaced by the URI of the currently selected OSC 8 hyperlink,
              or a question mark if no hyperlink is selected.  This is used by
              OSC 8 handlers as explained in the ^O^O command description.

       %pX    Replaced by the percent into the current input file, based on
              byte offsets.  The line used is determined by the X as with the
              %b option.

       %PX    Replaced by the percent into the current input file, based on
              line numbers.  The line used is determined by the X as with the
              %b option.

       %s     Same as %B.

       %t     Causes any trailing spaces to be removed.  Usually used at the
              end of the string, but may appear anywhere.

       %T     Normally expands to the word "file".  However if viewing files
              via a tags list using the -t option, it expands to the word
              "tag".

       %x     Replaced by the name of the next input file in the list.

       If any item is unknown (for example, the file size if input is a pipe),
       a question mark is printed instead.

       The format of the prompt string can be changed depending on certain
       conditions.  A question mark followed by a single character acts like
       an "IF": depending on the following character, a condition is
       evaluated.  If the condition is true, any characters following the
       question mark and condition character, up to a period, are included in
       the prompt.  If the condition is false, such characters are not
       included.  A colon appearing between the question mark and the period
       can be used to establish an "ELSE": any characters between the colon
       and the period are included in the string if and only if the IF
       condition is false.  Condition characters (which follow a question
       mark) may be:

       ?a     True if any characters have been included in the prompt so far.

       ?bX    True if the byte offset of the specified line is known.

       ?B     True if the size of current input file is known.

       ?c     True if the text is horizontally shifted (%c is not zero).

       ?dX    True if the page number of the specified line is known.

       ?e     True if at end-of-file.

       ?f     True if there is an input filename (that is, if input is not a
              pipe).

       ?lX    True if the line number of the specified line is known.

       ?L     True if the line number of the last line in the file is known.

       ?m     True if there is more than one input file.

       ?n     True if this is the first prompt in a new input file.

       ?pX    True if the percent into the current input file, based on byte
              offsets, of the specified line is known.

       ?PX    True if the percent into the current input file, based on line
              numbers, of the specified line is known.

       ?s     Same as "?B".

       ?x     True if there is a next input file (that is, if the current
              input file is not the last one).

       Any characters other than the special ones (question mark, colon,
       period, percent, and backslash) become literally part of the prompt.
       Any of the special characters may be included in the prompt literally
       by preceding it with a backslash.

       Some examples:

       ?f%f:Standard input.

       This prompt prints the filename, if known; otherwise the string
       "Standard input".

       ?f%f .?ltLine %lt:?pt%pt\%:?btByte %bt:-...

       This prompt would print the filename, if known.  The filename is
       followed by the line number, if known, otherwise the percent if known,
       otherwise the byte offset if known.  Otherwise, a dash is printed.
       Notice how each question mark has a matching period, and how the %
       after the %pt is included literally by escaping it with a backslash.

       ?n?f%f .?m(%T %i of %m) ..?e(END) ?x- Next\: %x..%t

       This prints the filename if this is the first prompt in a file,
       followed by the "file N of N" message if there is more than one input
       file.  Then, if we are at end-of-file, the string "(END)" is printed
       followed by the name of the next file, if there is one.  Finally, any
       trailing spaces are truncated.  This is the default prompt.  For
       reference, here are the defaults for the other two prompts (-m and -M
       respectively).  Each is broken into two lines here for readability
       only.

       ?n?f%f .?m(%T %i of %m) ..?e(END) ?x- Next\: %x.:
            ?pB%pB\%:byte %bB?s/%s...%t

       ?f%f .?n?m(%T %i of %m) ..?ltlines %lt-%lb?L/%L. :
            byte %bB?s/%s. .?e(END) ?x- Next\: %x.:?pB%pB\%..%t

       And here is the default message produced by the = command:

       ?f%f .?m(%T %i of %m) .?ltlines %lt-%lb?L/%L. .
            byte %bB?s/%s. ?e(END) :?pB%pB\%..%t

       The prompt expansion features are also used for another purpose: if an
       environment variable LESSEDIT is defined, it is used as the command to
       be executed when the v command is invoked.  The LESSEDIT string is
       expanded in the same way as the prompt strings.  The default value for
       LESSEDIT is:

            %E ?lm+%lm. %g

       Note that this expands to the editor name, followed by a + and the line
       number, followed by the shell-escaped file name.  If your editor does
       not accept the "+linenumber" syntax, or has other differences in
       invocation syntax, the LESSEDIT variable can be changed to modify this
       default.


SECURITY

       When the environment variable LESSSECURE is set to 1, less runs in a
       "secure" mode.  In this mode, these features are disabled:

       edit      the edit command (v)

       examine   the examine command (:e)

       glob      metacharacters such as * in filenames,
                 and filename completion (TAB, ^L)

       history   history file

       lesskey   use of lesskey files (-k and --lesskey-src)

       lessopen  input preprocessor (LESSOPEN environment variable)

       logfile   log files (s and -o)

       osc8      opening OSC 8 links (^O^O)

       pipe      the pipe command (|)

       shell     the shell and pshell commands (! and #)

       stop      stopping less via a SIGSTOP signal

       tags      use of tags files (-t)

       The LESSSECURE_ALLOW environment variable can be set to a comma-
       separated list of names of features which are selectively enabled when
       LESSSECURE is set.  Each feature name is the first word in each line in
       the above list.  A feature name may be abbreviated as long as the
       abbreviation is unambiguous.  For example, if LESSSECURE=1 and
       LESSSECURE_ALLOW=hist,edit were set, all of the above features would be
       disabled except for history files and the edit command.

       Less can also be compiled to be permanently in "secure" mode.  In that
       case, the LESSSECURE and LESSSECURE_ALLOW variables are ignored.


COMPATIBILITY WITH MORE

       If the environment variable LESS_IS_MORE is set to 1, or if the program
       is invoked via a file link named "more", less behaves (mostly) in
       conformance with the POSIX more(1) command specification.  In this
       mode, less behaves differently in these ways:

       The -e option works differently.  If the -e option is not set, less
       behaves as if the -e option were set.  If the -e option is set, less
       behaves as if the -E option were set.

       The -m option works differently.  If the -m option is not set, the
       medium prompt is used, and it is prefixed with the string "--More--".
       If the -m option is set, the short prompt is used.

       The -n option acts like the -z option.  The normal behavior of the -n
       option is unavailable in this mode.

       The parameter to the -p option is taken to be a less command rather
       than a search pattern.

       The LESS environment variable is ignored, and the MORE environment
       variable is used in its place.


ENVIRONMENT VARIABLES

       Environment variables may be specified either in the system environment
       as usual, or in a lesskey(1) file.  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.

       COLUMNS
              Sets the number of columns on the screen.  Takes precedence over
              the number of columns specified by the TERM variable.  (But if
              you have a windowing system which supports TIOCGWINSZ or
              WIOCGETD, the window system's idea of the screen size takes
              precedence over the LINES and COLUMNS environment variables.)

       EDITOR The name of the editor (used for the v command).

       HOME   Name of the user's home directory (used to find a lesskey file
              on Unix and OS/2 systems).

       HOMEDRIVE, HOMEPATH
              Concatenation of the HOMEDRIVE and HOMEPATH environment
              variables is the name of the user's home directory if the HOME
              variable is not set (only in the Windows version).

       INIT   Name of the user's init directory (used to find a lesskey file
              on OS/2 systems).

       LANG   Language for determining the character set.

       LC_CTYPE
              Language for determining the character set.

       LESS   Options which are passed to less automatically.

       LESSANSIENDCHARS
              Characters which may end an ANSI color escape sequence (default
              "m").

       LESSANSIMIDCHARS
              Characters which may appear between the ESC character and the
              end character in an ANSI color escape sequence (default
              "0123456789:;[?!"'#%()*+ ".

       LESSBINFMT
              Format for displaying non-printable, non-control characters.

       LESSCHARDEF
              Defines a character set.

       LESSCHARSET
              Selects a predefined character set.

       LESSCLOSE
              Command line to invoke the (optional) input-postprocessor.

       LESSECHO
              Name of the lessecho program (default "lessecho").  The lessecho
              program is needed to expand metacharacters, such as * and ?, in
              filenames on Unix systems.

       LESSEDIT
              Editor prototype string (used for the v command).  See
              discussion under PROMPTS.

       LESSGLOBALTAGS
              Name of the command used by the -t option to find global tags.
              Normally should be set to "global" if your system has the
              global(1) command.  If not set, global tags are not used.

       LESSHISTFILE
              Name of the history file used to remember search commands and
              shell commands between invocations of less.  If set to "-" or
              "/dev/null", a history file is not used.  The default depends on
              the operating system, but is usually:

              Linux and Unix
                     "$XDG_STATE_HOME/lesshst" or "$HOME/.local/state/lesshst"
                     or "$XDG_DATA_HOME/lesshst" or "$HOME/.lesshst".

              Windows and MS-DOS
                     "$HOME/_lesshst".

              OS/2   "$HOME/lesshst.ini" or "$INIT/lesshst.ini".

       LESSHISTSIZE
              The maximum number of commands to save in the history file.  The
              default is 100.

       LESSKEYIN
              Name of the default lesskey source file.

       LESSKEY
              Name of the default lesskey binary file. (Not used if
              "$LESSKEYIN" exists.)

       LESSKEY_CONTENT
              The value is parsed as if it were the parameter of a --lesskey-
              content option.

       LESSKEYIN_SYSTEM
              Name of the default system-wide lesskey source file.

       LESSKEY_SYSTEM
              Name of the default system-wide lesskey binary file. (Not used
              if "$LESSKEYIN_SYSTEM" exists.)

       LESSMETACHARS
              List of characters which are considered "metacharacters" by the
              shell.

       LESSMETAESCAPE
              Prefix which less will add before each metacharacter in a
              command sent to the shell.  If LESSMETAESCAPE is an empty
              string, commands containing metacharacters will not be passed to
              the shell.

       LESSOPEN
              Command line to invoke the (optional) input-preprocessor.

       LESSSECURE
              Runs less in "secure" mode.  See discussion under SECURITY.

       LESSSECURE_ALLOW
              Enables individual features which are normally disabled by
              LESSSECURE.  See discussion under SECURITY.

       LESSSEPARATOR
              String to be appended to a directory name in filename
              completion.

       LESSUTFBINFMT
              Format for displaying non-printable Unicode code points.

       LESSUTFCHARDEF
              Overrides the type of specified Unicode characters.

       LESS_COLUMNS
              Sets the number of columns on the screen.  Unlike COLUMNS, takes
              precedence over the system's idea of the screen size, so it can
              be used to make less use less than the full screen width.  If
              set to a negative number, sets the number of columns used to
              this much less than the actual screen width.

       LESS_LINES
              Sets the number of lines on the screen.  Unlike LINES, takes
              precedence over the system's idea of the screen size, so it can
              be used to make less use less than the full screen height.  If
              set to a negative number, sets the number of lines used to this
              much less than the actual screen height.  When set, less
              repaints the entire screen on every movement command, so
              scrolling may be slower.

       LESS_DATA_DELAY
              Duration (in milliseconds) after starting to read data from the
              input, after which the "Waiting for data" message will be
              displayed.  The default is 4000 (4 seconds).

       LESS_IS_MORE
              Emulate the more(1) command.

       LESS_OSC8_xxx
              Where "xxx" is a URI scheme such as "http" or "file", sets an
              OSC 8 handler for opening OSC 8 links containing a URI with that
              scheme.

       LESS_OSC8_ANY
              Sets an OSC 8 handler for opening OSC 8 links for which there is
              no specific LESS_OSC8_xxx handler set for the "xxx" scheme.

       LESS_TERMCAP_xx
              Where "xx" is any two characters, overrides the definition of
              the termcap "xx" capability for the terminal.

       LESS_UNSUPPORT
              A space-separated list of command line options.  These options
              will be ignored (with no error message) if they appear on the
              command line or in the LESS environment variable.  Options
              listed in LESS_UNSUPPORT can still be changed by the - and --
              commands.  Each option in LESS_UNSUPPORT is a dash followed by a
              single character option letter, or two dashes followed by a long
              option name.

       LINES  Sets the number of lines on the screen.  Takes precedence over
              the number of lines specified by the TERM variable.  (But if you
              have a windowing system which supports TIOCGWINSZ or WIOCGETD,
              the window system's idea of the screen size takes precedence
              over the LINES and COLUMNS environment variables.)

       MORE   Options which are passed to less automatically when running in
              more-compatible mode.

       PATH   User's search path (used to find a lesskey file on MS-DOS,
              Windows, and OS/2 systems).

       SHELL  The shell used to execute the ! command, as well as to expand
              filenames.

       TERM   The type of terminal on which less is being run.

       VISUAL The name of the editor (used for the v command).

       XDG_CONFIG_HOME
              Possible location of the lesskey file; see the KEY BINDINGS
              section.

       XDG_DATA_HOME
              Possible location of the history file; see the description of
              the LESSHISTFILE environment variable.

       XDG_STATE_HOME
              Possible location of the history file; see the description of
              the LESSHISTFILE environment variable.


SEE ALSO

       lesskey(1), lessecho(1)


COPYRIGHT

       Copyright (C) 1984-2024  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 MERCHANTABILITY or
       FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
       for more details.


AUTHOR

       Mark Nudelman
       Report bugs at https://github.com/gwsw/less/issues.
       For more information, see the less homepage at
       https://greenwoodsoftware.com/less.

                           Version 661: 29 Jun 2024                    less(1)

less 661 - Generated Sat Aug 17 19:03:55 CDT 2024
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