less(1) — Linux manual page

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LESS(1)                  General Commands Manual                 LESS(1)

NAME         top

       less - opposite of more

SYNOPSIS         top

       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         top

       Less is a program similar to more(1), but which allows backward
       movement in the file as well as forward movement.  Also, 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         top

       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.

       ?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.

       = 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 six 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.  On Unix systems, the shell is taken from the
              environment variable SHELL, or defaults to "sh".  On MS-
              DOS 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.

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

       ^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         top

       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, you don't need the quotes, but you should replace any
       percent signs in the options string by double percent signs.

       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="Dn9.1$Ds4.1"

       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.

              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.

              W      The highlight enabled via the -w option.

              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 "d" and "u" letters refer to
              bold and underline text formed by overstriking with
              backspaces (see the -U option), not to text using ANSI
              escape sequences with the -R option.

              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 zero, 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.  On MS-DOS versions
              of less, 8-bit color is not supported; instead, decimal
              values are interpreted as 4-bit CHAR_INFO.Attributes
              values (see
              https://docs.microsoft.com/en-us/windows/console/char-info-str).

              On MS-DOS only, the -Da option may be used to specify
              strict parsing of ANSI color (SGR) sequences when the -R
              option is used.  Without this option, sequences that
              change text attributes (bold, underline, etc.) may clear
              the text color.

       -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 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.

       --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.

       -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=N[,M]
              Sets the number of header lines and columns displayed on
              the screen.  The value may be of the form "N,M" where N
              and M are integers, to set the header lines to N and the
              header columns to M, or it may be a single integer "N"
              which sets the header lines to N and the header columns to
              zero, or it may be ",M" which sets the header columns to M
              and the header lines to zero.  When N is nonzero, the
              first N lines at the top of the screen are replaced with
              the first N lines of the file, regardless of what part of
              the file are being viewed.  When M is nonzero, the
              characters displayed at the beginning of each line are
              replaced with the first M characters of the line, even if
              the rest of the line is scrolled horizontally.  If either
              N or M is zero, less stops displaying header lines or
              columns, respectively.  (Note that it may be necessary to
              change the setting of the -j option to ensure that the
              target line is not obscured by the header line(s).)

       --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.

       --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, and clicking the mouse sets the "#"
              mark to the line where the mouse is clicked.  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-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 ECMA-48 SGR; see
              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         top

       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 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)
              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         top

       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         top

       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         top

       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 1251).

       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 latin1.

       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         top

       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.

       %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         top

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

              !      the shell command

              #      the pshell command

              |      the pipe command

              :e     the examine command.

              v      the editing command

              s  -o  log files

              -k     use of lesskey files

              -t     use of tags files

                     metacharacters in filenames, such as *

                     filename completion (TAB, ^L)

                     history file

       Less can also be compiled to be permanently in "secure" mode.

COMPATIBILITY WITH MORE         top

       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         top

       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.)

       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.

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

       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
              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         top

       lesskey(1), lessecho(1)

COPYRIGHT         top

       Copyright (C) 1984-2023  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         top

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

COLOPHON         top

       This page is part of the less (A file pager) project.
       Information about the project can be found at 
       ⟨http://www.greenwoodsoftware.com/less/⟩.  If you have a bug
       report for this manual page, see
       ⟨http://www.greenwoodsoftware.com/less/faq.html#bugs⟩.  This page
       was obtained from the tarball less-643.tar.gz fetched from
       ⟨http://www.greenwoodsoftware.com/less/download.html⟩ on
       2023-12-22.  If you discover any rendering problems in this HTML
       version of the page, or you believe there is a better or more up-
       to-date source for the page, or you have corrections or
       improvements to the information in this COLOPHON (which is not
       part of the original manual page), send a mail to
       man-pages@man7.org

                        Version 643: 20 Jul 2023                 LESS(1)

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