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LESS(1) 										  LESS(1)

NAME
       less - opposite of more

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

DESCRIPTION
       Less  is  a program similar to more (1), but 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
       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.

       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  behav-
	      ior is similar to the "tail -f" command.)

       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.)

       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 { com-
	      mand 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 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 for-
	      ward 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 back-
	      ward to the < which matches the > in the bottom 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 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.

       /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 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 cur-
		     rent 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  set-
		     tings 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 tex-
		     tual 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 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 pre-
	      vious 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 com-
	      mand, 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 tex-
		     tual 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.   Simi-
	      larly,  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  let-
	      ter.

       -!     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  set-
	      ting.  This does not work for numeric or string-valued options.

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

       _      (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 four commands may or may not be valid, depending on your particular  instal-
       lation.

       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  sys-
	      tems, 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 section 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  run-
       ning, via the "-" command.

       Most  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 over-
       ride 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 on MS-DOS like this:

       LESS="Dn9.1$Ds4.1"

       If the --use-backslash option appears earlier in the options, then a dollar sign or  back-
       slash  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 kilo-
	      bytes  (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 specified 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, 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.

       -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 (with status 2) when an interrupt  character  (usu-
	      ally  ^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), 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 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.

       -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 dis-
	      played 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 appearance 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 char-
	      acters 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 shown.  The default is to wrap 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
	      command	is   executed	to   find   the   tag.	  (See	 http://www.gnu.org/soft-
	      ware/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 equiv-
	      alent 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 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.   Text which is overstruck or underlined 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  com-
	      mand.   The  highlight  is  removed at the next command which causes movement.  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 sometimes desirable if the deinitialization  string  does  some-
	      thing 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  screen-
	      ful.  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.	If the number n is  nega-
	      tive,  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 contain-
	      ing 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 char-
	      acter.  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 num-
	      ber 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, so that the actual  scroll  remains
	      at the specified fraction of the screen width.

       --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.

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

       --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.

       --     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 previ-
	      ously 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 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"  charac-
       ter,  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  com-
	      mand 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 DOW-
	      NARROW, 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
       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 "$HOME/.less".  On MS-DOS and Win-
       dows systems, less looks for a lesskey file called "$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 system-wide file.  If the  environment  vari-
       able  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  sys-
       less  file  is  found.)	 On  MS-DOS  and Windows 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 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 pre-
       processor 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 pre-
       processor.  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  com-
       pressed 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 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 stan-
       dard 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 ver-
       tical 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
	    *)	 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 becomes  meaningful.   If	the  exit
       status is zero, the output is considered to be replacement text, even if it empty.  If the
       exit status is nonzero, any output is ignored and the original file is used.  For compati-
       bility  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.

       There are used following files to set up default preprocessor:
	    /etc/profile.d/less.sh
	    /etc/profile.d/less.csh
       These files set up /usr/bin/lesspipe.sh as a default filter. An user defined filter can be
       specified  in  ~/.lessfilter. This file should have an execute bit set and accept only one
       parameter, which represents a filename. If the user defined filter process the file,  zero
       should be returned. Otherwise ~/.lessfilter tries to handle the file.

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 charac-
       ter 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 con-
       trol, 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 val-
       ues 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  char-
       acter  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.   Other-
       wise,  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 sur-
       rounded 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, illegal octets, and stray
       trailing octets) are displayed individually using LESSBINFMT so as to facilitate  diagnos-
       tic 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 constructing 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 dis-
	      play  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.

       %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.

       %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 ques-
       tion 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 num-
       ber, if known, otherwise the percent if known, otherwise the byte offset if known.  Other-
       wise, 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  broken
       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 vari-
       able 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  unavail-
       able in this mode.

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

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

ENVIRONMENT VARIABLES
       Environment variables may be specified either in the system environment as usual, or in	a
       lesskey	(1) file.  If environment variables are defined in more than one place, variables
       defined in a local lesskey file take precedence over variables defined in the system envi-
       ronment, 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 col-
	      umns 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 ver-
	      sion).

       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 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 system's idea of the screen  size  takes  prece-
	      dence 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).

SEE ALSO
       lesskey(1)

COPYRIGHT
       Copyright (C) 1984-2012	Mark Nudelman

       less is part of the GNU project and is free software.  You can redistribute it and/or mod-
       ify  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  dis-
       tribution  for  more details regarding redistribution.  You should have received a copy of
       the GNU General Public License along with the source for less; see the file  COPYING.   If
       not,  write  to	the  Free  Software  Foundation,  59  Temple Place, Suite 330, Boston, MA
       02111-1307, USA.  You should also have received a copy of the Less License; see	the  file
       LICENSE.

       less  is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without
       even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
       GNU General Public License for more details.

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

				     Version 458: 04 Apr 2013				  LESS(1)
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