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LESS(1)			    General Commands Manual		       LESS(1)

NAME
       less - opposite of more

SYNOPSIS
       less -?
       less --help
       less -V
       less --version
       less [-[+]aBcCdeEfFgGiIJKmMnNqQrRsSuUVwWXZ~]
	    [-b	space] [-h lines] [-j line] [-k	keyfile]
	    [-K	character set] [-{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	 move-
       ment 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  "ES-
       CAPE", 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  be-
	      low).  If	N is more than the screen size,	only the final screen-
	      ful 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.

       RETURN or ^N or e or ^E or j or ^J
	      Scroll  forward N	lines, default 1.  The entire N	lines are dis-
	      played, 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  be-
	      low).  If	N is more than the screen size,	only the final screen-
	      ful 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 dis-
	      played, 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  be-
	      comes  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  be-
	      comes 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).	(Warn-
	      ing: 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.	(Warn-
	      ing: 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.

       {      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 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	brack-
	      ets.

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

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

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

       m      Followed by any lowercase	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.  Fol-
	      lowed  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  '  com-
	      mand 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 pat-
	      tern.  N defaults	to 1.  The pattern is a	regular	expression, as
	      recognized  by  ed.   The	 search	starts at the second line dis-
	      played (but see the -a and -j options, which change this).

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

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

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

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

	      ^K     Highlight any text	which matches the pattern on the  cur-
		     rent screen, but don't move to the	first match (KEEP cur-
		     rent 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 dis-
		     played on the screen or the settings of the -a or -j  op-
		     tions.

	      ^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 pat-
	      tern.  If	the previous search was	modified by ^N,	the search  is
	      made  for	the N-th line NOT containing the pattern.  If the pre-
	      vious 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  ef-
	      fect is as if the	previous search	were modified by *.

       ESC-N  Repeat  previous search, but in the reverse direction and	cross-
	      ing 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.)

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

       ^X^V or E
	      Same  as :e.  Warning: some systems use ^V as a special literal-
	      ization 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 com-
	      mand 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.

       @      Rotate  the  code	 recognition  method of	the current file.  En-
	      hanced less has 7	methods	for  recognition,  default  (which  is
	      chosen  by  the  JLESSCHARSET  environment  variable), japanese,
	      ujis, sjis, iso8,	noconv and none.

       -      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  en-
	      tered  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 set-
	      ting 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 RE-
	      TURN 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 re-
	      set  the	option	to its default setting and print a message de-
	      scribing the new setting.	 (The  "-+X"  command  does  the  same
	      thing  as	 "-+X"	on  the	command	line.)	This does not work for
	      string-valued options.

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

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

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

       _      (Underscore.)   Followed	by one of the command line option let-
	      ters, 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 variable VISUAL if defined,
	      or EDITOR	if VISUAL is not defined, or defaults to "vi" if  nei-
	      ther  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 exam-
	      ined  file.   "!!"  repeats the last shell command.  "!" with no
	      shell command simply invokes a  shell.   On  Unix	 systems,  the
	      shell  is	taken from the environment variable SHELL, or defaults
	      to "sh".	On MS-DOS and OS/2 systems, the	shell  is  the	normal
	      command processor.

       | <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	 indi-
	      cate beginning or	end of file respectively.  If <m> is . or new-
	      line, 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 "-" 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  un-
       ambiguous.   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  let-
       ter  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"  and
       "JLESS".	  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  per-
       cent 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 and JLESS	environment variables.	If  an
       option  appears in the LESS and JLESS variables,	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 in-
	      terprets 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 de-
	      fault, 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 is 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	 allo-
	      cated.  The -B option disables this automatic allocation of buf-
	      fers for pipes, so that only 64K (or the amount of space	speci-
	      fied 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 file	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
	      The -C option is like -c,	but the	screen is cleared before it is
	      repainted.

       -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 sin-
	      gle character which selects the type of text whose color is  be-
	      ing  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.0.

       -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 warn-
	      ing message when a binary	file is	opened.	 By default, less will
	      refuse to	open non-regular files.

       -F or --quit-if-one-screen
	      Causes less to automatically exit	if the entire file can be dis-
	      played 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 high-
	      light only the particular	string which was  found	 by  the  last
	      search command.  This can	cause less to run somewhat faster than
	      the default.

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

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

       -i or --ignore-case
	      Causes searches to ignore	case; that is, uppercase and lowercase
	      are  considered identical.  This option is ignored if any	upper-
	      case 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.  A target line is the	object of a text  search,  tag
	      search,  jump  to	 a  line number, jump to a file	percentage, or
	      jump to a	marked position.  The screen line is  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.  If the -j option  is
	      used,  searches  begin  at the line immediately after the	target
	      line.  For example, if "-j4" is used, the	 target	 line  is  the
	      fourth  line  on the screen, so 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  ef-
	      fect.

       -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.

       -Kcharset
	      Causes  less to use this charset instead of a charset defined in
	      the JLESSCHARSET or LESSCHARSET environment variable.

       -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 op-
	      tion will	avoid this problem.  Using  line  numbers  means:  the
	      line number will be displayed in the verbose prompt and in the =
	      command, and the v command will pass the current line number  to
	      the  editor  (see	also the discussion of LESSEDIT	in PROMPTS be-
	      low).

       -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	occur-
	      rence 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 and
	      JLESS environment	variables, rather than	being  typed  in  with
	      each  less  command.  Such an option must	either be the last op-
	      tion in the LESS and JLESS variables, or be terminated by	a dol-
	      lar  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 ex-
	      ample, 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 dis-
	      play problems may	result,	such as	long lines being split in  the
	      wrong place.

       -R or --RAW-CONTROL-CHARS
	      Like  -r,	but tries to keep track	of the screen appearance where
	      possible.	 This works only if the	input consists of normal  text
	      and  possibly  some ANSI "color" escape sequences, which are se-
	      quences of the form:

		   ESC [ ... m

	      where the	"..." is zero or more characters other than "m".   For
	      the  purpose  of keeping track of	screen appearance, all control
	      characters and all 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 charac-
	      ters which can end a color escape	sequence.

       -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 remainder of a	long  line  is	simply
	      discarded.   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  di-
	      rectory  called  "tags", which was previously built by ctags (1)
	      or an equivalent command.	 If the	environment variable LESSGLOB-
	      ALTAGS  is set, it is taken to be	the name of a command compati-
	      ble with global (1), and that command is executed	 to  find  the
	      tag.  (See http://www.gnu.org/software/global/global.html).  The
	      -t option	may also be specified from within less	(using	the  -
	      command)	as a way of examining a	new file.  The command ":t" is
	      equivalent to specifying -t from within less.

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

       -u or --underline-special
	      Causes backspaces	and carriage returns to	be treated  as	print-
	      able  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  ap-
	      pear  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 capabil-
	      ity.  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 imme-
	      diately 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 con-
	      tinue with the same spacing  as  the  last  two.	 For  example,
	      -x9,17  will  set	tabs at	positions 9, 17, 25, 33, etc.  The de-
	      fault for	n is 8.

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

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

       -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 re-
	      painted  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 de-
	      fault is one screenful.  The z and w commands can	also  be  used
	      to  change the window size.  The "z" may be omitted for compati-
	      bility with 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 auto-
	      matically	changes	to 36 lines.

       -Z     Causes to	give priority to the SJIS over the UJIS	 if  a	"japa-
	      nese"  was  selected  by	the JLESSCHARSET environment variable.
	      The default value	is to give priority to the UJIS	over the SJIS.

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

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

       -# or --shift
	      Specifies	the default number of positions	to scroll horizontally
	      in the RIGHTARROW	and LEFTARROW commands.	 If the	number	speci-
	      fied  is	zero,  it  sets	the default number of positions	to one
	      half of the screen width.

       --     A	command	line argument of "--" marks the	end  of	 option	 argu-
	      ments.   Any  arguments  following this are interpreted as file-
	      names.  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 ev-
	      ery  file	 being	viewed,	not just the first one.	 The + command
	      described	previously may also be used to set (or change) an ini-
	      tial 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), cer-
       tain  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.  (The bracketed forms do not work
       in the MS-DOS version.)	Any of these special keys may be entered  lit-
       erally  by  preceding it	with the "literal" character, either ^V	or ^A.
       A backslash itself may also be entered literally	by entering two	 back-
       slashes.

       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 cur-
	      sor one word to the left.

       ^RIGHTARROW [ ESC-w or ESC-RIGHTARROW ]
	      (That is,	CONTROL	and RIGHTARROW simultaneously.)	 Move the cur-
	      sor 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 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 char-
	      acter 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 de-
       tails.

       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 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 systems, 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  Windows  systems, the system-wide lesskey file is c:\_sys-
       less.  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  sim-
       ply  an executable program (or shell script), which writes the contents
       of the file to a	different file,	called the replacement file.  The con-
       tents  of  the replacement file are then	displayed in place of the con-
       tents 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 replace-
       ment filename, less uses	the original file, as normal.  The input  pre-
       processor  is not called	when viewing standard input.  To set up	an in-
       put 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  re-
       placed by the filename when the input preprocessor command is invoked.

       When less closes	a file opened in such a	way, it	will call another pro-
       gram, 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 orig-
       inal  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  re-
       placed  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 -c $1  >/tmp/less.$$  2>/dev/null
		 if [ -s /tmp/less.$$ ]; 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	start-
       ing 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  replace-
       ment file on its	standard output, writes	the entire contents of the re-
       placement file on its standard output.  If  the	input  pipe  does  not
       write  any characters on	its standard output, then there	is no replace-
       ment 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 pre-
       vious 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 "-".

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	JLESSCHARSET and LESS-
       CHARSET environment variables may be used to select  a  character  set.
       There  is no difference between them in program of less.	 But I suppose
       you should use the JLESSCHARSET environment variable  because  not  en-
       hanced  less will make errors if	you use	enhanced character set in your
       LESSCHARSET environment variable.  Possible values for them 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.

       Possible	values for only	JLESSCHARSET are:

       iso7   Multi character sets with	the ISO	2022 code extension techniques
	      in 7 bits	are assumed.  Characters with values between  128  and
	      255  are treated as binary.  The level of	implementation of Less
	      is level 3 of ISO	2022.

       iso8   Multi character sets with	the ISO	2022 code extension techniques
	      in  8  bits are assumed.	The level of implementation of Less is
	      level 3 of ISO 2022.

       jis    Only Japanese character sets with	the ISO	 2022  code  extension
	      techniques in 7 bits are assumed.

       ujis   If characters has	values between 32 and 127, the ASCII character
	      set are assumed.	If characters has values between 162 and  254,
	      the JISX 0208 character set, a right half	of the JISX 0201 char-
	      acter set	and the	JISX 0212 character set	with the  UJIS	coding
	      are assumed.  Otherwise, characters are treated as binary.

       euc    Same as ujis.

       sjis   If characters has	values between 32 and 127, the ASCII character
	      set are assumed.	If characters has values between 128 and  252,
	      the  JISX	 0208  character set and a right half of the JISX 0201
	      character	set are	assumed.  Otherwise, characters	are treated as
	      binary.

       japanese
	      All  Japanese  character	sets, jis, ujis	and sjis, are assumed.
	      But less output only the jis.

       Japanese	has several code sets (not character sets).   Thus  less  must
       convert	among  them  to	 display them correctly.  Possible values with
       this conversion for only	JLESSCHARSET are:

       ujis-iso7
	      The ujis and iso7	are assumend.  But less	output only the	iso7.

       euc-iso7
	      Same as ujis-iso7.

       sjis-iso7
	      The sjis and iso7	are assumend.  But less	output only the	iso7.

       ujis-jis
	      The ujis and jis are assumend.  But less output only the jis.

       euc-jis
	      Same as ujis-jis.

       sjis-jis
	      The sjis and jis are assumend.  But less output only the jis.

       jis-ujis
	      The jis and ujis are assumend.  But less output only the ujis.

       jis-euc
	      Same as jis-ujis.

       jis-sjis
	      The jis and sjis are assumend.  But less output only the sjis.

       japanese-iso7
	      The japanese and iso7 are	assumend.  But less  output  only  the
	      iso7.

       japanese-jis
	      The  japanese  is	assumend.  But less output only	the jis.  Same
	      as japanese.

       japanese-ujis
	      The japanese is assumend.	 But less output only the ujis.

       japanese-euc
	      Same as japanese-ujis.

       japanese-sjis
	      The japanese is assumend.	 But less output only the sjis.

       ujis-sjis
	      The ujis is assumend.  But less output only the sjis.

       euc-sjis
	      Same as ujis-sjis.

       sjis-ujis
	      The sjis is assumend.  But less output only the ujis.

       sjis-euc
	      Same as sjis-ujis.

       Other way to select a character set is  to  use	the  LANG  environment
       variable.   If it start with "ja_JP" or "japan",	less read all Japanese
       coded characters	as some	Japanese character set,	and a rest of the LANG
       environment variable specify output coding.

       The  ISO	2022 code extension techniques define 4	planes to display many
       character sets easy.  Default setting of	 planes	 is  selected  by  the
       JLESSPLANESET  environment  variable.   If the JLESSPLANESET vriable is
       equal to	"japanese", "ujis" or "euc", less treat	g1 plane as JISX 0208,
       g2  plane  as  JISX  0201  right	half, g3 plane as JISX 0212.  If it is
       equal to	"latin1", "latin2",  "latin3",	"latin4",  "greek",  "alabic",
       "hebrew",  "cyrillic"  or  "latin5",  less treat	g1 plane as one	of ISO
       8859.  Otherwise, less try to parse the JLESSPLANESET variable as  real
       escape  sequences  for setting up, and "\e" in JLESSPLANESET is treated
       as escape code when parsing.

       Less understand almost all escape sequence about	character set  in  the
       ISO 2022	code extension techniques.  There are many escape sequences to
       select the character set.  On the one hand, less	output only  6	escape
       sequences to select a character set: '^[(', '^[-', '^[$(', '^[$-', '^N'
       and '^O'.  It means less	is friendly to a terminal and a	terminal  emu-
       lator.

       And  there is special "character	set" for keyboard inputs.  The JLESSK-
       EYCHARSET environment variable is used for such purpose.	 Possible val-
       ues of it are equal to the JLESSCHARSET environment variable.

       In  special  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	repre-
       sents  one  character  in the character set.  The character "." is used
       for a normal character, "c" for control,	and "b"	for binary.  A decimal
       number  may  be used for	repetition.  For example, "bccc4b." would mean
       character 0 is binary, 1, 2 and 3 are control, 4, 5, 6 and  7  are  bi-
       nary,  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 char-
       acter 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 the  string  "UTF-8"
       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 in-
       terface,	 less will use setlocale to determine the character set.  set-
       locale is controlled by setting the LANG	or LC_CTYPE environment	 vari-
       ables.

       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 char-
       acter is	displayed as a hex number in angle brackets.  This format  can
       be  changed by setting the LESSBINFMT environment variable.  LESSBINFMT
       may begin with a	"*" and	one character to select	the display attribute:
       "*k"  is	 blinking, "*d"	is bold, "*u" is underlined, "*s" is standout,
       and "*n"	is normal.  If LESSBINFMT does not begin with  a  "*",	normal
       attribute  is  assumed.	 The remainder of LESSBINFMT is	a string which
       may include one printf-style escape sequence (a % followed by x,	X,  o,
       d,  etc.).   For	 example, if LESSBINFMT	is "*u[%x]", binary characters
       are displayed in	underlined hexadecimal surrounded  by  brackets.   The
       default if no LESSBINFMT	is specified is	"*s<%X>".

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	 ordi-
       nary  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 spec-
	      ifies  the line whose byte offset	is to be used.	If the charac-
	      ter 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 bot-
	      tom 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  equiva-
	      lently, 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	anywhere.

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

       %K     Replaced by the name of the last non ASCII character set or code
	      set.

       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	evalu-
       ated.   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  in-
	      put file is not the last one).

       Any  characters	other than the special ones (question mark, colon, pe-
       riod, 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	"Stan-
       dard input".

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

       This  prompt  would print the filename, if known.  The filename is fol-
       lowed by	the line number, if known, otherwise  the  percent  if	known,
       otherwise the byte offset if known.  Otherwise, a dash is printed.  No-
       tice 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, fol-
       lowed 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	refer-
       ence, here are the defaults for the other two prompts (-m  and  -M  re-
       spectively).  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 variable LESSEDIT is	defined, it is used as the command  to
       be  executed when the v command is invoked.  The	LESSEDIT string	is ex-
       panded 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.

ENVIRONMENT VARIABLES
       Environment variables may be specified either in	the system environment
       as usual, or in a lesskey (1) file.  If environment variables  are  de-
       fined in	more than one place, variables defined in a local lesskey file
       take precedence over variables defined in the system environment, which
       take precedence over variables defined in the system-wide lesskey file.

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

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

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

       HOMEDRIVE, HOMEPATH
	      Concatenation of the HOMEDRIVE and  HOMEPATH  environment	 vari-
	      ables is the name	of the user's home directory if	the HOME vari-
	      able 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.

       JLESS  same as the LESS environment variable.

       LESSANSIENDCHARS
	      Characters  which	 are  assumed  to end an ANSI color escape se-
	      quence (default "m").

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

       LESSCHARDEF
	      Defines a	character set.

       JLESSCHARSET
	      Selects a	predefined character set.

       LESSCHARSET
	      Selects a	predefined character set if JLESSCHARSET  is  not  de-
	      fined.

       JLESSKEYCHARSET
	      Selects a	predefined character set for keyboard inputs.

       JLESSPLANESET
	      Selects  a  predefined  plane set	of the ISO 2022	code extension
	      techniques.

       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  discus-
	      sion 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.

       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  com-
	      mand  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 comple-
	      tion.

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

       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)

WARNINGS
       The = command and prompts (unless changed by -P)	report the  line  num-
       bers of the lines at the	top and	bottom of the screen, but the byte and
       percent of the line after the one at the	bottom of the screen.

       If the :e command is used to name more than one file, and  one  of  the
       named  files  has  been viewed previously, the new files	may be entered
       into the	list in	an unexpected order.

       On certain older	terminals (the so-called  "magic  cookie"  terminals),
       search  highlighting  will  cause an erroneous display.	On such	termi-
       nals, search highlighting is disabled  by  default  to  avoid  possible
       problems.

       In certain cases, when search highlighting is enabled and a search pat-
       tern begins with	a ^, more text than the	matching string	may  be	 high-
       lighted.	 (This problem does not	occur when less	is compiled to use the
       POSIX regular expression	package.)

       When viewing text containing ANSI color escape sequences	using  the  -R
       option,	searching will not find	text containing	an embedded escape se-
       quence.	Also, search highlighting may change the color of some of  the
       text which follows the highlighted text.

       On  some	 systems, setlocale claims that	ASCII characters 0 thru	31 are
       control characters rather than binary characters.  This causes less  to
       treat  some  binary files as ordinary, non-binary files.	 To workaround
       this problem, set the environment variable LESSCHARSET to  "ascii"  (or
       whatever	character set is appropriate).

       See  http://www.greenwoodsoftware.com/less for the latest list of known
       bugs in this version of less.

COPYRIGHT
       Copyright (C) 2002  Mark	Nudelman
       Copyright  (c)  1994,1995,1996,1997,1998	   Kazushi   (Jam)   Marukawa,
       Japanized routines only

       less  is	 part of the GNU project and is	free software.	You can	redis-
       tribute it and/or modify	it under the terms of either (1) the GNU  Gen-
       eral  Public  License  as published by the Free Software	Foundation; or
       (2) the Less License.  See the file README in the less distribution for
       more details regarding redistribution.  You should have received	a copy
       of the GNU General Public License along with the	source for  less;  see
       the  file  COPYING.   If	not, write to the Free Software	Foundation, 59
       Temple Place, Suite 330,	Boston,	MA  02111-1307,	USA.  You should  also
       have received a copy of the Less	License; see the file LICENSE.

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

AUTHOR
       Mark Nudelman <markn@greenwoodsoftware.com>
       jam@pobox.com
       Send  bug  reports  or  comments	 to  the  above	 address  or  to  bug-
       less@gnu.org.
       For  more  information,	see the	less homepage at http://www.greenwood-
       software.com/less.

			   Version 378:	30 Sep 2002		       LESS(1)

NAME | SYNOPSIS | DESCRIPTION | COMMANDS | OPTIONS | LINE EDITING | KEY BINDINGS | INPUT PREPROCESSOR | NATIONAL CHARACTER SETS | PROMPTS | SECURITY | ENVIRONMENT VARIABLES | SEE ALSO | WARNINGS | COPYRIGHT | AUTHOR

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