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LESS(1)                                                                LESS(1)



NAME
       less - opposite of more

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


DESCRIPTION
       Less  is a program similar to more (1), but which allows backward movement in the file as well as forward move-
       ment.  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 descrip-
       tions below.  The number is used by some commands, as indicated.


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

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

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

       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.

       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.

       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.

       r or ^R or ^L
              Repaint the screen.

       R      Repaint  the  screen,  discarding  any buffered input.  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.)

       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.)

       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 top line, a number N may be used to spec-
              ify 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, respec-
              tively.   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, respec-
              tively.  For example, "ESC ^B < >" could be used to go backward to the < which matches the > in the bot-
              tom displayed line.

       m      Followed by any lowercase letter, marks the current position with that letter.

       '      (Single quote.)  Followed by any lowercase 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  respec-
              tively.  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.

       /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.  The search
              starts at the second 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 find-
                     ing 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.

       ?pattern
              Search backward in the file for the N-th line containing the pattern.  The search  starts  at  the  line
              immediately before the top line displayed.

              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.

       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 mod-
              ified  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 mod-
              ified 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.)

       &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.

              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  consecu-
              tive  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 sev-
              eral 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 num-
              ber 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 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 com-
              mand 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 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 four 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 vari-
              able  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  sys-
              tems,  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.

       | <m> shell-command
              <m> represents any mark letter.  Pipes a section of the input file to the given shell command.  The sec-
              tion  of the file to be piped is between the first line on the current screen and the position marked by
              the letter.  <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 only works if the input is a pipe, not an ordinary file.


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

       Most options may be given in one of two forms: either a dash followed by a single letter, or  two  dashes  fol-
       lowed 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 "-+".

       For  options  like  -P or -D which take a following string, a dollar sign ($) must be used to signal the end of
       the string.  For example, to set two -D options on MS-DOS, you must have a dollar sign between them, like this:

       LESS="-Dn9.1$-Ds4.1"


       -? 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
              Causes  searches to start after the last line displayed on the screen, thus skipping all lines displayed
              on the screen.  By default, searches start at the second line on the screen (or  after  the  last  found
              line; see the -j option).

       -bn or --buffers=n
              Specifies  the  amount  of buffer space less will use for each file, in units of kilobytes (1024 bytes).
              By default 64K 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 64K (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.

       -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
              [MS-DOS only] Sets the color of the text displayed.  x is a single character which selects the  type  of
              text  whose color is being set: n=normal, s=standout, d=bold, u=underlined, k=blink.  color is a pair of
              numbers separated by a period.  The first number selects the foreground color and the second selects the
              background  color  of  the text.  A single number N is the same as N.M, where M is the normal background
              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.

       --old-bot
              Reverts to the old bottom of screen behavior.  This can be sometimes desirable  if  the  long lines  are
              not wrapped  correctly when  reaching  the  bottom  of  the  terminal,  while scrolling forward.

       -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 speci-
              fied as a fraction, the actual line number is recalculated if the terminal window is  resized,  so  that
              the target line remains at the specified fraction of the screen height.  If any form of the -j option is
              used, forward searches begin at the line immediately after the target line, and backward searches  begin
              at the target line.  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.

       -J or --status-column
              Displays a status column at the left edge of the screen.  The status column shows the lines that matched
              the current search.  The status column is also used if the -w or -W option is in effect.

       -kfilename or --lesskey-file=filename
              Causes  less  to  open  and  interpret the named file as a lesskey (1) 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.

       -K or --quit-on-intr
              Causes  less to exit immediately when an interrupt character (usually ^C) is typed.  Normally, an inter-
              rupt 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 cur-
              rently open.

       -m or --long-prompt
              Causes  less  to prompt verbosely (like more), 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.

       -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 discus-
              sion 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 equiv-
              alent 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.

       -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".  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.

       -R or --RAW-CONTROL-CHARS
              Like -r, but only ANSI "color" escape sequences are output in "raw" form.  Unlike -r, the screen appear-
              ance is maintained correctly in most cases.  ANSI "color" escape sequences are sequences of the form:

                   ESC [ ... m

              where the "..." is zero or more color specification characters For  the  purpose  of  keeping  track  of
              screen  appearance,  ANSI  color escape sequences are assumed to not move the cursor.  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 rather than folded.  That is, the portion  of  a
              long  line  that does not fit in the screen width is not shown.  The default is to fold long lines; that
              is, display the remainder on the next line.

       -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 com-
              mand 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 com-
              mand ":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 and carriage returns to be treated as control characters; that is, they are han-
              dled 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 capa-
              bility.  Also, backspaces which appear between two identical characters are treated specially: the over-
              struck 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.  Text which is overstruck or under-
              lined can be searched for if neither -u nor -U is in effect.

       -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 move-
              ment.   The entire 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 some-
              times 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.

       -[z]n or --window=n
              Changes  the  default scrolling window size to n lines.  The default is one screenful.  The z and w com-
              mands can also be used to change the window size.  The "z" may be omitted for  compatibility  with  some
              versions  of more.  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  charac-
              ter,  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  com-
              mands.   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, start-
              ing 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,  so  that the actual scroll remains at the specified fraction of the
              screen width.

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

       --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.

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

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


LINE EDITING
       When entering command line at the bottom of the screen (for example, a filename for the :e command, or the pat-
       tern  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 char-
       acter.)  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.

       DOWNARROW [ ESC-j ]
              Retrieve the next command line.

       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  file-
              names.   If  the  completed filename is a directory, a "/" is appended to the filename.  (On MS-DOS sys-
              tems, 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.


KEY BINDINGS
       You  may  define  your  own less commands by using the program lesskey (1) to create a lesskey file.  This file
       specifies a set of command keys and an action associated with each key.  You may also use lesskey to change the
       line-editing keys (see LINE EDITING), and to set environment variables.  If the environment variable LESSKEY is
       set, less uses that as the name of the lesskey file.  Otherwise, less looks in a standard place for the lesskey
       file: On Unix systems, less looks for a lesskey file called "$HOME/.less".  On MS-DOS and Windows systems, less
       looks for a lesskey file called "$HOME/_less", and if it is not found there, then  looks  for  a  lesskey  file
       called  "_less" in any directory specified in the PATH environment variable.  On OS/2 systems, less looks for a
       lesskey file called "$HOME/less.ini", and if it is not found, then looks for a lesskey file  called  "less.ini"
       in  any  directory  specified  in  the  INIT  environment variable, and if it not found there, then looks for a
       lesskey file called "less.ini" in any directory specified in the PATH environment variable.   See  the  lesskey
       manual page for more details.

       A  system-wide  lesskey  file  may also be set up to provide key bindings.  If a key is defined in both a local
       lesskey file and in the system-wide file, key bindings in the local file take precedence over those in the sys-
       tem-wide  file.   If  the environment variable LESSKEY_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  sys-
       tems,  the  system-wide  lesskey  file is /usr/local/etc/sysless.  (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  Win-
       dows  systems,  the  system-wide lesskey file is c:\_sysless.  On OS/2 systems, the system-wide lesskey file is
       c:\sysless.ini.


INPUT PREPROCESSOR
       You may define an "input preprocessor" for less.  Before less opens a file, it first gives your  input  prepro-
       cessor  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  dis-
       play 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 nor-
       mal.  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) uncompress -
                 if [ -s /tmp/less.$$ ]; then
                      echo /tmp/less.$$
                 else
                      rm -f /tmp/less.$$
                 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  LESS-
       CLOSE="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.

       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
                 ;;
            esac

       To use this script, put it where it can be executed and set LESSOPEN="|lesspipe.sh %s".  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 sin-
       gle dash.  Similarly, if the first two characters of LESSOPEN are vertical bar and dash (|-), the input pipe is
       used  on  standard  input as well as other files.  Again, in this case the dash is not considered to be part of
       the input pipe command.


NATIONAL CHARACTER SETS
       There are three types of characters in the input file:

       normal characters
              can be displayed directly to the screen.

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

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

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

       ascii  BS,  TAB, NL, CR, and formfeed are control characters, all chars with values between 32 and 126 are nor-
              mal, 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 LESS-
       CHARSET.  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 char-
       acter "." 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_TYPE 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 brack-
       ets.   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 set-
       ting,  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, illegal octets, and stray trailing octets) are displayed individ-
       ually using LESSBINFMT so as to facilitate diagnostic of how the UTF-8 file is ill-formed.


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

       A percent sign followed by a single character is expanded according to what the following character is:

       %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.

       %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  any-
              where.

       %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 liter-
       ally 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, other-
       wise 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(file %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 bro-
       ken into two lines here for readability only.

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

       ?f%f .?n?m(file %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(file %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. %f

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


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

              !      the shell 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)

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


COMPATIBILITY WITH MORE
       If  the  environment  variable  LESS_IS_MORE  is  set  to 1, or if the program is invoked via a file link named
       "more", less behaves (mostly) in conformance with the POSIX "more" 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 and -F options were set.

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

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

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

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


ENVIRONMENT VARIABLES
       Environment variables may be specified either in the system environment as usual, or in a lesskey (1) file.  If
       environment variables are defined in more than one place, variables defined in a local lesskey file take prece-
       dence  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  direc-
              tory 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 metacharac-
              ters, 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 is "$HOME/.lesshst" on
              Unix systems, "$HOME/_lesshst" on DOS and Windows systems, or "$HOME/lesshst.ini" or "$INIT/lesshst.ini"
              on OS/2 systems.

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

       LESSKEY
              Name of the default lesskey(1) file.

       LESSKEY_SYSTEM
              Name of the default system-wide lesskey(1) file.

       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.

       LESS_IS_MORE
              Emulate the more (1) command.

       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 sys-
              tem's idea of the screen size takes precedence over the LINES and COLUMNS environment variables.)

       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).


SEE ALSO
       lesskey(1)


COPYRIGHT
       Copyright (C) 1984-2009  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 war-
       ranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU  General  Public  License  for  more
       details.


AUTHOR
       Mark Nudelman <marknATgreenwoodsoftware.com>
       See http://www.greenwoodsoftware.com/less/bugs.html for the latest list of known bugs in less.
       Send bug reports or comments to the above address or to
       bug-lessATgnu.org.
       For more information, see the less homepage at
       http://www.greenwoodsoftware.com/less.



                           Version 436: 07 Jul 2009                    LESS(1)