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LESS(1)								       LESS(1)

NAME
       less - opposite of more

SYNOPSIS
       less -?
       less --help
       less -V
       less --version
       less [-[+]aBcCdeEfFgGiIJLmMnNqQrRsSuUVwWX~]
	    [-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	 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
       "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  spe-
	      cial 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
	      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 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
	      becomes  the  default  for  future RIGHTARROW and	LEFTARROW com-
	      mands.  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 com-
	      mands.

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

       ^X^V or E
	      Same as :e.  Warning: some systems use ^V	as a special  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.

       -      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 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
	      RETURN after typing the option name.  A ^P immediately after the
	      second  dash suppresses printing of a message describing the new
	      setting, as in the - command.

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

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

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

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

       _      (Underscore.)   Followed	by one of the command line option 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
       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  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".  For exam-
       ple, 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  environment  variable.	If  an	option
       appears	in  the	LESS variable, it can be reset to its default value on
       the command line	by beginning the command line option with "-+".

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

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

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

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

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

       -L or --no-lessopen
	      Ignore the LESSOPEN environment variable	(see  the  INPUT  PRE-
	      PROCESSOR	 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	 discussion  of	 LESSEDIT  in  PROMPTS
	      below).

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

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

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

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

       -ppattern or --pattern=pattern
	      The  -p  option  on the command line is equivalent to specifying
	      +/pattern; that is, it tells less	to start at the	 first	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 envi-
	      ronment variable,	rather than being typed	in with	each less com-
	      mand.  Such an option must either	be the last option in the LESS
	      variable,	 or be terminated by a dollar sign.  -Ps followed by a
	      string changes the default (short) prompt	to that	 string.   -Pm
	      changes  the  medium  (-m)  prompt.   -PM	 changes the long (-M)
	      prompt.  -Ph changes  the	 prompt	 for  the  help	 screen.   -P=
	      changes  the  message printed by the = command.  -Pw changes the
	      message printed while waiting for	data (in the F command).   All
	      prompt  strings  consist	of  a  sequence	of letters and special
	      escape sequences.	 See the section on PROMPTS for	more  details.

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

       -Q or --QUIET or	--SILENT
	      Causes totally "quiet" operation:	the  terminal  bell  is	 never
	      rung.

       -r or --raw-control-chars
	      Causes "raw" control characters to be displayed.	The default is
	      to display control characters  using  the	 caret	notation;  for
	      example, a control-A (octal 001) is displayed as "^A".  Warning:
	      when the -r option is used, less cannot keep track of the	actual
	      appearance  of  the screen (since	this depends on	how the	screen
	      responds to each type of control character).  Thus, various 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
	      sequences	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 portion of a long line that does not
	      fit in the screen	width is not shown.  The default  is  to  fold
	      long lines; that is, display the remainder on the	next line.

       -ttag or	--tag=tag
	      The -t option, followed immediately by a TAG, will edit the file
	      containing that tag.  For	this to	work, tag information must  be
	      available;  for  example,	 there	may  be	 a file	in the current
	      directory	called "tags", which was previously built by ctags (1)
	      or an equivalent command.	 If the	environment variable 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
	      appear adjacent to an  underscore	 character  are	 treated  spe-
	      cially:  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	 bold-
	      face  capability.	  Other	backspaces are deleted,	along with the
	      preceding	character.  Carriage returns immediately followed by a
	      newline  are  deleted.   other  carriage	returns	are handled as
	      specified	by the -r option.  Text	which is overstruck or	under-
	      lined can	be searched for	if neither -u nor -U is	in effect.

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

       -w or --hilite-unread
	      Temporarily  highlights  the  first  "new"  line after a forward
	      movement of a full page.	The first "new"	line is	the line 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
	      default for n is 8.

       -X or --no-init
	      Disables sending the termcap initialization and deinitialization
	      strings  to  the	terminal.   This is sometimes desirable	if the
	      deinitialization string does something unnecessary, like	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
	      repainted	instead.  The -c or -C option may be used  to  repaint
	      from  the	top of the screen if desired.  By default, any forward
	      movement causes scrolling.

       -[z]n or	--window=n
	      Changes the default scrolling  window  size  to  n  lines.   The
	      default is one screenful.	 The z and w 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.

       -"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
	      every 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
       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 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
       input  preprocessor, set	the LESSOPEN environment variable to a command
       line which will invoke your  input  preprocessor.   This	 command  line
       should  include	one  occurrence	 of  the  string  "%s",	 which will be
       replaced	by  the	 filename  when	 the  input  preprocessor  command  is
       invoked.

       When less closes	a file opened in such a	way, it	will call another 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
       replaced	 with  the  original  name of the file and the second with the
       name of the replacement file, which was output by LESSOPEN.

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

       lessopen.sh:
	    #! /bin/sh
	    case "$1" in
	    *.Z) uncompress -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
       replacement  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  LESSCHARSET  environment
       variable	 may  be  used to select a character set.  Possible values for
       LESSCHARSET are:

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

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

       latin1 Same as iso8859.

       latin9 Same as iso8859.

       dos    Selects a	character set appropriate for MS-DOS.

       ebcdic Selects an EBCDIC	character set.

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

       koi8-r Selects a	Russian	character set.

       next   Selects a	character set appropriate for NeXT computers.

       utf-8  Selects the UTF-8	encoding of the	ISO 10646 character set.

       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
       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 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
       interface, less will use	setlocale  to  determine  the  character  set.
       setlocale  is  controlled  by  setting the LANG or LC_CTYPE environment
       variables.

       Finally,	if the setlocale interface is also not available, the  default
       character set is	latin1.

       Control	and  binary  characters	 are  displayed	 in  standout (reverse
       video).	Each such character is displayed in caret notation if possible
       (e.g.  ^A for control-A).  Caret	notation is used only if inverting the
       0100 bit	results	in a normal printable character.  Otherwise, the 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.

       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
	      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	"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.
       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, 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
       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  variable LESSEDIT is defined, it is	used as	the command to
       be executed when	the v command is  invoked.   The  LESSEDIT  string  is
       expanded	 in the	same way as the	prompt strings.	 The default value for
       LESSEDIT	is:

	    %E ?lm+%lm.	%f

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

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

	      !	     the shell command

	      |	     the pipe command

	      :e     the examine command.

	      v	     the editing command

	      s	 -o  log files

	      -k     use of lesskey files

	      -t     use of tags files

		     metacharacters in filenames, such as *

		     filename completion (TAB, ^L)

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

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

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

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

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

       HOMEDRIVE, HOMEPATH
	      Concatenation of the HOMEDRIVE and  HOMEPATH  environment	 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.

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

       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  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
       sequence.  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

       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>
       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 381:	17 Jan 2003		       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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