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LESS(1)  										    LESS(1) 

NAME
       less - opposite of more

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

DESCRIPTION
       Less  is  a program similar to more (1), but which allows backward movement in the file as
       well as forward movement.  Also, less does not have to read the entire input  file  before
       starting,  so  with  large  input files it starts up faster than text editors like vi (1).
       Less uses termcap (or terminfo on some systems), so it can run on a variety of  terminals.
       There  is  even	limited  support  for hardcopy terminals.  (On a hardcopy terminal, lines
       which should be printed at the top of the screen are prefixed with a caret.)

       Commands are based on both more and vi.	Commands may be preceded  by  a  decimal  number,
       called N in the descriptions below.  The number is used by some commands, as indicated.

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

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

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

       z      Like SPACE, but if N is specified, it becomes the new window size.

       ESC-SPACE
	      Like  SPACE,  but  scrolls  a full screenful, even if it reaches end-of-file in the
	      process.

       ENTER or RETURN or ^N or e or ^E or j or ^J
	      Scroll forward N lines, default 1.  The entire N lines are displayed, even if N  is
	      more than the screen size.

       d or ^D
	      Scroll forward N lines, default one half of the screen size.  If N is specified, it
	      becomes the new default for subsequent d and u commands.

       b or ^B or ESC-v
	      Scroll backward N lines, default one window (see option -z below).  If  N  is  more
	      than the screen size, only the final screenful is displayed.

       w      Like ESC-v, but if N is specified, it becomes the new window size.

       y or ^Y or ^P or k or ^K
	      Scroll backward N lines, default 1.  The entire N lines are displayed, even if N is
	      more than the screen size.  Warning: some systems use ^Y as a special  job  control
	      character.

       u or ^U
	      Scroll  backward	N lines, default one half of the screen size.  If N is specified,
	      it becomes the new default for subsequent d and u commands.

       ESC-) or RIGHTARROW
	      Scroll horizontally right N characters, default half the screen width (see  the  -#
	      option).	 If a number N is specified, it becomes the default for future RIGHTARROW
	      and LEFTARROW commands.  While the text is scrolled,  it	acts  as  though  the  -S
	      option (chop lines) were in effect.

       ESC-( or LEFTARROW
	      Scroll  horizontally  left  N characters, default half the screen width (see the -#
	      option).	If a number N is specified, it becomes the default for future  RIGHTARROW
	      and LEFTARROW commands.

       r or ^R or ^L
	      Repaint the screen.

       R      Repaint  the screen, discarding any buffered input.  Useful if the file is changing
	      while it is being viewed.

       F      Scroll forward, and keep trying to read when the end of file is reached.	 Normally
	      this  command  would  be	used when already at the end of the file.  It is a way to
	      monitor the tail of a file which is growing while it is being viewed.  (The  behav-
	      ior is similar to the "tail -f" command.)

       g or < or ESC-<
	      Go  to  line  N  in the file, default 1 (beginning of file).  (Warning: this may be
	      slow if N is large.)

       G or > or ESC->
	      Go to line N in the file, default the end of the file.  (Warning: this may be  slow
	      if  N is large, or if N is not specified and standard input, rather than a file, is
	      being read.)

       p or % Go to a position N percent into the file.  N should be between 0 and 100,  and  may
	      contain a decimal point.

       P      Go to the line containing byte offset N in the file.

       {      If a left curly bracket appears in the top line displayed on the screen, the { com-
	      mand will go to the matching right curly bracket.  The matching right curly bracket
	      is  positioned  on  the  bottom line of the screen.  If there is more than one left
	      curly bracket on the top line, a number N may be used to specify the  N-th  bracket
	      on the line.

       }      If  a right curly bracket appears in the bottom line displayed on the screen, the }
	      command will go to the matching  left  curly  bracket.   The  matching  left  curly
	      bracket  is  positioned  on  the top line of the screen.	If there is more than one
	      right curly bracket on the top line, a number N may be used  to  specify	the  N-th
	      bracket on the line.

       (      Like {, but applies to parentheses rather than curly brackets.

       )      Like }, but applies to parentheses rather than curly brackets.

       [      Like {, but applies to square brackets rather than curly brackets.

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

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

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

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

       '      (Single  quote.)	 Followed  by any lowercase letter, returns to the position which
	      was previously marked with that letter.  Followed by another single quote,  returns
	      to  the position at which the last "large" movement command was executed.  Followed
	      by a ^ or $, jumps to the beginning or end of the  file  respectively.   Marks  are
	      preserved  when  a  new  file  is  examined, so the ' command can be used to switch
	      between input files.

       ^X^X   Same as single quote.

       /pattern
	      Search forward in the file for the N-th line containing the pattern.  N defaults to
	      1.   The	pattern  is a regular expression, as recognized by the regular expression
	      library supplied by your system.	The search starts at  the  first  line	displayed
	      (but see the -a and -j options, which change this).

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

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

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

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

	      ^K     Highlight any text which matches the pattern  on  the  current  screen,  but
		     don't move to the first match (KEEP current position).

	      ^R     Don't interpret regular expression metacharacters; that is, do a simple tex-
		     tual comparison.

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

	      Certain characters are special as in the / command:

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

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

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

	      ^K     As in forward searches.

	      ^R     As in forward searches.

       ESC-/pattern
	      Same as "/*".

       ESC-?pattern
	      Same as "?*".

       n      Repeat previous search, for N-th line containing the last pattern.  If the previous
	      search was modified by ^N, the search is made for the N-th line NOT containing  the
	      pattern.	 If  the  previous search was modified by ^E, the search continues in the
	      next (or previous) file if not satisfied in the  current	file.	If  the  previous
	      search  was  modified  by ^R, the search is done without using regular expressions.
	      There is no effect if the previous search was modified by ^F or ^K.

       N      Repeat previous search, but in the reverse direction.

       ESC-n  Repeat previous search, but crossing file boundaries.  The effect is as if the pre-
	      vious search were modified by *.

       ESC-N  Repeat previous search, but in the reverse direction and crossing file boundaries.

       ESC-u  Undo  search  highlighting.   Turn off highlighting of strings matching the current
	      search pattern.  If highlighting is already off because of a  previous  ESC-u  com-
	      mand,  turn  highlighting  back on.  Any search command will also turn highlighting
	      back on.	(Highlighting can also be disabled by toggling the  -G	option;  in  that
	      case search commands do not turn highlighting back on.)

       &pattern
	      Display  only  lines  which match the pattern; lines which do not match the pattern
	      are not displayed.  If pattern is empty (if you  type  &	immediately  followed  by
	      ENTER),  any filtering is turned off, and all lines are displayed.  While filtering
	      is in effect, an ampersand is displayed at  the  beginning  of  the  prompt,  as	a
	      reminder that some lines in the file may be hidden.

	      Certain characters are special as in the / command:

	      ^N or !
		     Display only lines which do NOT match the pattern.

	      ^R     Don't interpret regular expression metacharacters; that is, do a simple tex-
		     tual comparison.

       :e [filename]
	      Examine a new file.  If the filename is missing, the "current" file (see the :n and
	      :p  commands  below)  from the list of files in the command line is re-examined.	A
	      percent sign (%) in the filename is replaced by the name of the  current	file.	A
	      pound  sign  (#) is replaced by the name of the previously examined file.  However,
	      two consecutive percent signs are simply replaced with a single percent sign.  This
	      allows  you  to  enter  a filename that contains a percent sign in the name.  Simi-
	      larly, two consecutive pound signs are replaced with  a  single  pound  sign.   The
	      filename	is inserted into the command line list of files so that it can be seen by
	      subsequent :n and :p commands.  If the filename consists of several files, they are
	      all inserted into the list of files and the first one is examined.  If the filename
	      contains one or more spaces, the entire  filename  should  be  enclosed  in  double
	      quotes (also see the -" option).

       ^X^V or E
	      Same  as	:e.   Warning: some systems use ^V as a special literalization character.
	      On such systems, you may not be able to use ^V.

       :n     Examine the next file (from the list of files given in the  command  line).   If	a
	      number N is specified, the N-th next file is examined.

       :p     Examine  the  previous  file in the command line list.  If a number N is specified,
	      the N-th previous file is examined.

       :x     Examine the first file in the command line list.	If a number N is  specified,  the
	      N-th file in the list is examined.

       :d     Remove the current file from the list of files.

       t      Go  to  the next tag, if there were more than one matches for the current tag.  See
	      the -t option for more details about tags.

       T      Go to the previous tag, if there were more than one matches for the current tag.

       = or ^G or :f
	      Prints some information about the file being viewed, including  its  name  and  the
	      line  number  and  byte offset of the bottom line being displayed.  If possible, it
	      also prints the length of the file, the number of lines in the file and the percent
	      of the file above the last displayed line.

       -      Followed	by  one of the command line option letters (see OPTIONS below), this will
	      change the setting of that option and print a message describing the  new  setting.
	      If  a  ^P  (CONTROL-P)  is  entered  immediately after the dash, the setting of the
	      option is changed but no message is printed.  If the option letter  has  a  numeric
	      value  (such as -b or -h), or a string value (such as -P or -t), a new value may be
	      entered after the option letter.	If no new value is entered, a message  describing
	      the current setting is printed and nothing is changed.

       --     Like  the - command, but takes a long option name (see OPTIONS below) rather than a
	      single option letter.  You must press ENTER or RETURN after typing the option name.
	      A  ^P immediately after the second dash suppresses printing of a message describing
	      the new setting, as in the - command.

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

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

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

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

       _      (Underscore.)   Followed by one of the command line option letters, this will print
	      a message describing the current setting of that option.	The setting of the option
	      is not changed.

       __     (Double underscore.)  Like the _ (underscore) command, but takes a long option name
	      rather than a single option letter.  You must press ENTER or  RETURN  after  typing
	      the option name.

       +cmd   Causes  the  specified  cmd  to  be executed each time a new file is examined.  For
	      example, +G causes less to initially display each file starting at the  end  rather
	      than the beginning.

       V      Prints the version number of less being run.

       q or Q or :q or :Q or ZZ
	      Exits less.

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

       v      Invokes an editor to edit the current file being viewed.	The editor is taken  from
	      the  environment variable VISUAL if defined, or EDITOR if VISUAL is not defined, or
	      defaults to "vi" if neither VISUAL nor EDITOR is defined.  See also the  discussion
	      of LESSEDIT under the section on PROMPTS below.

       ! shell-command
	      Invokes  a shell to run the shell-command given.	A percent sign (%) in the command
	      is replaced by the name of the current file.  A pound sign (#) is replaced  by  the
	      name  of	the  previously examined file.	"!!" repeats the last shell command.  "!"
	      with no shell command simply invokes a shell.  On Unix systems, the shell is  taken
	      from  the environment variable SHELL, or defaults to "sh".  On MS-DOS and OS/2 sys-
	      tems, the shell is the normal command processor.

       | <m> shell-command
	      <m> represents any mark letter.  Pipes a section of the input  file  to  the  given
	      shell  command.	The  section of the file to be piped is between the first line on
	      the current screen and the position marked by the letter.  <m> may also be ^  or	$
	      to  indicate  beginning  or  end of file respectively.  If <m> is . or newline, the
	      current screen is piped.

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

OPTIONS
       Command	line options are described below.  Most options may be changed while less is run-
       ning, via the "-" command.

       Most options may be given in one of two forms: either a dash followed by a single  letter,
       or  two	dashes	followed by a long option name.  A long option name may be abbreviated as
       long as the abbreviation is unambiguous.  For example, --quit-at-eof  may  be  abbreviated
       --quit,	but  not --qui, since both --quit-at-eof and --quiet begin with --qui.	Some long
       option names are in uppercase, such as  --QUIT-AT-EOF,  as  distinct  from  --quit-at-eof.
       Such option names need only have their first letter capitalized; the remainder of the name
       may be in either case.  For example, --Quit-at-eof is equivalent to --QUIT-AT-EOF.

       Options are also taken from the environment variable "LESS".  For example, to avoid typing
       "less -options ..." each time less is invoked, you might tell csh:

       setenv LESS "-options"

       or if you use sh:

       LESS="-options"; export LESS

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

       The environment variable is parsed before the command line, so command line options  over-
       ride  the LESS environment variable.  If an option appears in the LESS variable, it can be
       reset to its default value on the command line by beginning the command line  option  with
       "-+".

       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
	      By default, forward searches start at the top of the displayed screen and backwards
	      searches start at the bottom of the displayed screen (except for repeated  searches
	      invoked  by  the	n  or  N  commands, which start after or before the "target" line
	      respectively; see the -j option for more about the target  line).   The  -a  option
	      causes  forward  searches to instead start at the bottom of the screen and backward
	      searches to start at the top of the screen, thus skipping all  lines  displayed  on
	      the screen.

       -A or --SEARCH-SKIP-SCREEN
	      Causes  all  forward  searches (not just non-repeated searches) to start just after
	      the target line, and all backward searches to start just before  the  target  line.
	      Thus,  forward searches will skip part of the displayed screen (from the first line
	      up to and including the target line).  Similarly backwards searches will	skip  the
	      displayed  screen from the last line up to and including the target line.  This was
	      the default behavior in less versions prior to 441.

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

       -B or --auto-buffers
	      By default, when data is read from a pipe, buffers are allocated	automatically  as
	      needed.	If  a  large amount of data is read from the pipe, this can cause a large
	      amount of memory to be allocated.  The -B option disables this automatic allocation
	      of  buffers for pipes, so that only 64K (or the amount of space specified by the -b
	      option) is used for the pipe.  Warning: use of -B can result in erroneous  display,
	      since  only  the most recently viewed part of the piped data is kept in memory; any
	      earlier data is lost.

       -c or --clear-screen
	      Causes full screen repaints to be painted from the top line down.  By default, full
	      screen repaints are done by scrolling from the bottom of the screen.

       -C or --CLEAR-SCREEN
	      Same as -c, for compatibility with older versions of less.

       -d or --dumb
	      The  -d  option  suppresses the error message normally displayed if the terminal is
	      dumb; that is, lacks some important capability, such as the ability  to  clear  the
	      screen or scroll backward.  The -d option does not otherwise change the behavior of
	      less on a dumb terminal.

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

       -e or --quit-at-eof
	      Causes  less  to	automatically  exit  the  second time it reaches end-of-file.  By
	      default, the only way to exit less is via the "q" command.

       -E or --QUIT-AT-EOF
	      Causes less to automatically exit the first time it reaches end-of-file.

       -f or --force
	      Forces non-regular files to be opened.  (A non-regular file is  a  directory  or	a
	      device  special  file.)	Also suppresses the warning message when a binary file is
	      opened.  By default, less will refuse to open non-regular files.	 Note  that  some
	      operating systems will not allow directories to be read, even if -f is set.

       -F or --quit-if-one-screen
	      Causes  less to automatically exit if the entire file can be displayed on the first
	      screen.

       -g or --hilite-search
	      Normally, less will highlight ALL strings which match the last search command.  The
	      -g  option  changes this behavior to highlight only the particular string which was
	      found by the last search command.  This can cause less to run somewhat faster  than
	      the default.

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

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

       -i or --ignore-case
	      Causes searches to ignore case; that is, uppercase  and  lowercase  are  considered
	      identical.   This  option  is ignored if any uppercase letters appear in the search
	      pattern; in other words, if a pattern contains uppercase letters, then that  search
	      does not ignore case.

       -I or --IGNORE-CASE
	      Like -i, but searches ignore case even if the pattern contains uppercase letters.

       -jn or --jump-target=n
	      Specifies  a  line  on the screen where the "target" line is to be positioned.  The
	      target line is the line specified by any command to search for a pattern, jump to a
	      line  number,  jump  to a file percentage or jump to a tag.  The screen line may be
	      specified by a number: the top line on the screen is 1, the next is 2, and  so  on.
	      The  number may be negative to specify a line relative to the bottom of the screen:
	      the bottom line on the screen is -1, the second to the bottom is	-2,  and  so  on.
	      Alternately,  the  screen  line may be specified as a fraction of the height of the
	      screen, starting with a decimal point: .5 is in the middle of  the  screen,  .3  is
	      three  tenths  down  from the first line, and so on.  If the line is specified as a
	      fraction, the actual line number is recalculated if the terminal window is resized,
	      so that the target line remains at the specified fraction of the screen height.  If
	      any form of the -j option is used, forward searches begin at the	line  immediately
	      after  the  target  line,  and  backward	searches begin at the target line, unless
	      changed by -a or -A.  For example, if "-j4" is used, the target line is the  fourth
	      line on the screen, so forward searches begin at the fifth line on the screen.

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

       -kfilename or --lesskey-file=filename
	      Causes  less  to open and interpret the named file as a lesskey (1) file.  Multiple
	      -k options may be specified.  If the LESSKEY or LESSKEY_SYSTEM environment variable
	      is set, or if a lesskey file is found in a standard place (see KEY BINDINGS), it is
	      also used as a lesskey file.

       -K or --quit-on-intr
	      Causes less to exit immediately (with status 2) when an interrupt  character  (usu-
	      ally  ^C)  is typed.  Normally, an interrupt character causes less to stop whatever
	      it is doing and return to its command prompt.  Note that use of this  option  makes
	      it impossible to return to the command prompt from the "F" command.

       -L or --no-lessopen
	      Ignore  the  LESSOPEN  environment  variable  (see  the  INPUT PREPROCESSOR section
	      below).  This option can be set from within less, but it will apply only	to  files
	      opened subsequently, not to the file which is currently open.

       -m or --long-prompt
	      Causes  less  to	prompt verbosely (like more), with the percent into the file.  By
	      default, less prompts with a colon.

       -M or --LONG-PROMPT
	      Causes less to prompt even more verbosely than more.

       -n or --line-numbers
	      Suppresses line numbers.	The default (to use line numbers) may cause less  to  run
	      more  slowly  in	some cases, especially with a very large input file.  Suppressing
	      line numbers with the -n option will avoid this problem.	Using line numbers means:
	      the  line  number will be displayed in the verbose prompt and in the = command, and
	      the v command will pass the current line number to the editor (see also the discus-
	      sion of LESSEDIT in PROMPTS below).

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

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

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

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

       -ppattern or --pattern=pattern
	      The -p option on the command line is equivalent to specifying +/pattern;	that  is,
	      it tells less to start at the first occurrence of pattern in the file.

       -Pprompt or --prompt=prompt
	      Provides	a  way	to  tailor  the three prompt styles to your own preference.  This
	      option would normally be put in the LESS environment variable,  rather  than  being
	      typed  in with each less command.  Such an option must either be the last option in
	      the LESS variable, or be terminated by a dollar sign.  -Ps  followed  by	a  string
	      changes  the  default  (short)  prompt to that string.  -Pm changes the medium (-m)
	      prompt.  -PM changes the long (-M) prompt.  -Ph changes the  prompt  for	the  help
	      screen.  -P= changes the message printed by the = command.  -Pw changes the message
	      printed while waiting for data (in the F command).  All prompt strings consist of a
	      sequence	of  letters and special escape sequences.  See the section on PROMPTS for
	      more details.

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

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

       -r or --raw-control-chars
	      Causes "raw" control characters to be displayed.	The default is to display control
	      characters  using  the caret notation; for example, a control-A (octal 001) is dis-
	      played as "^A".  Warning: when the -r option is used, less cannot keep track of the
	      actual  appearance  of the screen (since this depends on how the screen responds to
	      each type of control character).	Thus, various display problems may  result,  such
	      as long lines being split in the wrong place.

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

		   ESC [ ... m

	      where  the  "..." is zero or more color specification characters For the purpose of
	      keeping track of screen appearance, ANSI color escape sequences are assumed to  not
	      move  the  cursor.   You can make less think that characters other than "m" can end
	      ANSI color escape sequences by setting the environment variable LESSANSIENDCHARS to
	      the  list  of  characters  which can end a color escape sequence.  And you can make
	      less think that characters other than the standard ones may appear between the  ESC
	      and the m by setting the environment variable LESSANSIMIDCHARS to the list of char-
	      acters which can appear.

       -s or --squeeze-blank-lines
	      Causes consecutive blank lines to be squeezed into a single blank  line.	 This  is
	      useful when viewing nroff output.

       -S or --chop-long-lines
	      Causes  lines  longer than the screen width to be chopped rather than folded.  That
	      is, the portion of a long line that does not fit in the screen width is not  shown.
	      The default is to fold long lines; that is, display the remainder on the next line.

       -ttag or --tag=tag
	      The  -t  option,	followed immediately by a TAG, will edit the file containing that
	      tag.  For this to work, tag information must be available; for example,  there  may
	      be  a  file  in  the current directory called "tags", which was previously built by
	      ctags (1) or an equivalent command.  If the environment variable LESSGLOBALTAGS  is
	      set,  it	is taken to be the name of a command compatible with global (1), and that
	      command	is   executed	to   find   the   tag.	  (See	 http://www.gnu.org/soft-
	      ware/global/global.html).   The  -t  option  may also be specified from within less
	      (using the - command) as a way of examining a new file.  The command ":t" is equiv-
	      alent to specifying -t from within less.

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

       -u or --underline-special
	      Causes  backspaces and carriage returns to be treated as printable characters; that
	      is, they are sent to the terminal when they appear in the input.

       -U or --UNDERLINE-SPECIAL
	      Causes backspaces, tabs and carriage returns to be treated as  control  characters;
	      that is, they are handled as specified by the -r option.

	      By  default,  if neither -u nor -U is given, backspaces which appear adjacent to an
	      underscore character are treated specially: the underlined text is displayed  using
	      the  terminal's  hardware  underlining  capability.   Also, backspaces which appear
	      between two identical characters are treated  specially:	the  overstruck  text  is
	      printed  using  the  terminal's hardware boldface capability.  Other backspaces are
	      deleted, along with the preceding character.  Carriage returns immediately followed
	      by  a  newline are deleted.  other carriage returns are handled as specified by the
	      -r option.  Text which is overstruck or underlined can be searched for  if  neither
	      -u nor -U is in effect.

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

       -w or --hilite-unread
	      Temporarily  highlights  the  first  "new"  line after a forward movement of a full
	      page.  The first "new" line is the line immediately following the  line  previously
	      at  the  bottom of the screen.  Also highlights the target line after a g or p com-
	      mand.  The highlight is removed at the next command  which  causes  movement.   The
	      entire  line  is highlighted, unless the -J option is in effect, in which case only
	      the status column is highlighted.

       -W or --HILITE-UNREAD
	      Like -w, but temporarily highlights the first new line after any	forward  movement
	      command larger than one line.

       -xn,... or --tabs=n,...
	      Sets  tab  stops.  If only one n is specified, tab stops are set at multiples of n.
	      If multiple values separated by commas are specified, tab stops are  set	at  those
	      positions,  and  then continue with the same spacing as the last two.  For example,
	      -x9,17 will set tabs at positions 9, 17, 25, 33, etc.  The default for n is 8.

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

       -yn or --max-forw-scroll=n
	      Specifies a maximum number of lines to scroll  forward.	If  it	is  necessary  to
	      scroll  forward  more  than n lines, the screen is repainted instead.  The -c or -C
	      option may be used to repaint from the top of the screen if desired.   By  default,
	      any forward movement causes scrolling.

       -[z]n or --window=n
	      Changes  the  default scrolling window size to n lines.  The default is one screen-
	      ful.  The z and w commands can also be used to change the window size.  The "z" may
	      be  omitted for compatibility with some versions of more.  If the number n is nega-
	      tive, it indicates n lines less than the current screen size.  For example, if  the
	      screen  is  24 lines, -z-4 sets the scrolling window to 20 lines.  If the screen is
	      resized to 40 lines, the scrolling window automatically changes to 36 lines.

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

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

       -# or --shift
	      Specifies  the default number of positions to scroll horizontally in the RIGHTARROW
	      and LEFTARROW commands.  If the number specified is zero, it sets the default  num-
	      ber  of  positions to one half of the screen width.  Alternately, the number may be
	      specified as a fraction of the width of the screen, starting with a decimal  point:
	      .5  is half of the screen width, .3 is three tenths of the screen width, and so on.
	      If the number is specified as a fraction, the actual number of scroll positions  is
	      recalculated  if	the terminal window is resized, so that the actual scroll remains
	      at the specified fraction of the screen width.

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

       --follow-name
	      Normally, if the input file is renamed while an F command is executing,  less  will
	      continue	to display the contents of the original file despite its name change.  If
	      --follow-name is specified, during an F command less will periodically  attempt  to
	      reopen  the  file by name.  If the reopen succeeds and the file is a different file
	      from the original (which means that a new file has been created with the same  name
	      as  the  original  (now  renamed) file), less will display the contents of that new
	      file.

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

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

LINE EDITING
       When entering command line at the bottom of the screen (for example, a filename for the :e
       command, or the pattern for a search command), certain keys can be used to manipulate  the
       command line.  Most commands have an alternate form in [ brackets ] which can be used if a
       key does not exist on a particular keyboard.  (Note that the forms beginning with  ESC  do
       not work in some MS-DOS and Windows systems because ESC is the line erase character.)  Any
       of these special keys may be entered literally by preceding it with the "literal"  charac-
       ter,  either  ^V  or ^A.  A backslash itself may also be entered literally by entering two
       backslashes.

       LEFTARROW [ ESC-h ]
	      Move the cursor one space to the left.

       RIGHTARROW [ ESC-l ]
	      Move the cursor one space to the right.

       ^LEFTARROW [ ESC-b or ESC-LEFTARROW ]
	      (That is, CONTROL and LEFTARROW simultaneously.)	Move the cursor one word  to  the
	      left.

       ^RIGHTARROW [ ESC-w or ESC-RIGHTARROW ]
	      (That  is, CONTROL and RIGHTARROW simultaneously.)  Move the cursor one word to the
	      right.

       HOME [ ESC-0 ]
	      Move the cursor to the beginning of the line.

       END [ ESC-$ ]
	      Move the cursor to the end of the line.

       BACKSPACE
	      Delete the character to the left of the cursor, or cancel the command if	the  com-
	      mand line is empty.

       DELETE or [ ESC-x ]
	      Delete the character under the cursor.

       ^BACKSPACE [ ESC-BACKSPACE ]
	      (That  is,  CONTROL  and BACKSPACE simultaneously.)  Delete the word to the left of
	      the cursor.

       ^DELETE [ ESC-X or ESC-DELETE ]
	      (That is, CONTROL and DELETE simultaneously.)  Delete the word under the cursor.

       UPARROW [ ESC-k ]
	      Retrieve the previous command line.

       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 character in Unix to something other than ^U,
	      that character is used instead of ^U.

       ^G     Delete the entire command line and return to the main prompt.

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

       A system-wide lesskey file may also be set up to  provide  key  bindings.   If  a  key  is
       defined	in  both  a  local  lesskey file and in the system-wide file, key bindings in the
       local file take precedence over those in the system-wide file.  If the  environment  vari-
       able  LESSKEY_SYSTEM  is  set, less uses that as the name of the system-wide lesskey file.
       Otherwise, less looks in a standard place for the system-wide lesskey file: On  Unix  sys-
       tems, the system-wide lesskey file is /usr/local/etc/sysless.  (However, if less was built
       with a different sysconf directory than /usr/local/etc, that directory is where	the  sys-
       less  file  is  found.)	 On  MS-DOS  and Windows systems, the system-wide lesskey file is
       c:\_sysless.  On OS/2 systems, the system-wide lesskey file is c:\sysless.ini.

INPUT PREPROCESSOR
       You may define an "input preprocessor" for less.  Before less opens a file, it first gives
       your input preprocessor a chance to modify the way the contents of the file are displayed.
       An input preprocessor is simply an executable program (or shell script), which writes  the
       contents  of  the  file to a different file, called the replacement file.  The contents of
       the replacement file are then displayed in place of the contents  of  the  original  file.
       However,  it will appear to the user as if the original file is opened; that is, less will
       display the original filename as the name of the current file.

       An input preprocessor receives one  command  line  argument,  the  original  filename,  as
       entered	by the user.  It should create the replacement file, and when finished, print the
       name of the replacement file to its standard output.  If the input preprocessor	does  not
       output  a  replacement  filename,  less uses the original file, as normal.  The input pre-
       processor is not called when viewing standard input.  To set up an input preprocessor, set
       the  LESSOPEN  environment  variable  to  a command line which will invoke your input pre-
       processor.  This command line should include one occurrence of the string "%s", which will
       be replaced by the filename when the input preprocessor command is invoked.

       When  less  closes  a  file opened in such a way, it will call another program, called the
       input postprocessor, which may perform any desired clean-up action (such as  deleting  the
       replacement  file created by LESSOPEN).	This program receives two command line arguments,
       the original filename as entered by the user, and the name of the  replacement  file.   To
       set  up	an  input postprocessor, set the LESSCLOSE environment variable to a command line
       which will invoke your input postprocessor.  It may include two occurrences of the  string
       "%s";  the  first  is  replaced with the original name of the file and the second with the
       name of the replacement file, which was output by LESSOPEN.

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

       lessopen.sh:
	    #! /bin/sh
	    case "$1" in
	    *.Z) uncompress -
		 if [ -s /tmp/less.$$ ]; then
		      echo /tmp/less.$$
		 else
		      rm -f /tmp/less.$$
		 fi
		 ;;
	    esac

       lessclose.sh:
	    #! /bin/sh
	    rm $2

       To   use   these   scripts,   put   them   both	 where	they  can  be  executed  and  set
       LESSOPEN="lessopen.sh %s", and LESSCLOSE="lessclose.sh %s %s".  More complex LESSOPEN  and
       LESSCLOSE scripts may be written to accept other types of compressed files, and so on.

       It  is  also  possible  to  set up an input preprocessor to pipe the file data directly to
       less, rather than putting the data into a replacement  file.   This  avoids  the  need  to
       decompress  the	entire file before starting to view it.  An input preprocessor that works
       this way is called an input pipe.  An input  pipe,  instead  of	writing  the  name  of	a
       replacement  file  on  its  standard output, writes the entire contents of the replacement
       file on its standard output.  If the input pipe does not write any characters on its stan-
       dard output, then there is no replacement file and less uses the original file, as normal.
       To use an input pipe, make the first character in the LESSOPEN environment variable a ver-
       tical bar (|) to signify that the input preprocessor is an input pipe.

       For  example,  on  many	Unix  systems,	this  script  will work like the previous example
       scripts:

       lesspipe.sh:
	    #! /bin/sh
	    case "$1" in
	    *.Z) uncompress -c $1  2>/dev/null
		 ;;
	    esac

       To use this script, put it where it can be executed and	set  LESSOPEN="|lesspipe.sh  %s".
       When  an  input pipe is used, a LESSCLOSE postprocessor can be used, but it is usually not
       necessary since there is no replacement file to clean up.  In this case,  the  replacement
       file name passed to the LESSCLOSE postprocessor is "-".

       For  compatibility  with  previous versions of less, the input preprocessor or pipe is not
       used if less is viewing standard input.	However, if the first character of LESSOPEN is	a
       dash  (-),  the	input  preprocessor is used on standard input as well as other files.  In
       this case, the dash is not considered to be part of the preprocessor command.  If standard
       input is being viewed, the input preprocessor is passed a file name consisting of a single
       dash.  Similarly, if the first two characters of LESSOPEN are vertical bar and dash  (|-),
       the  input pipe is used on standard input as well as other files.  Again, in this case the
       dash is not considered to be part of the input pipe command.

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

       normal characters
	      can be displayed directly to the screen.

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

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

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

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

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

       latin1 Same as iso8859.

       latin9 Same as iso8859.

       dos    Selects a character set appropriate for MS-DOS.

       ebcdic Selects an EBCDIC character set.

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

       koi8-r Selects a Russian character set.

       next   Selects a character set appropriate for NeXT computers.

       utf-8  Selects  the  UTF-8  encoding  of the ISO 10646 character set.  UTF-8 is special in
	      that it supports multi-byte characters in the input file.  It is the only character
	      set that supports multi-byte characters.

       windows
	      Selects a character set appropriate for Microsoft Windows (cp 1251).

       In rare cases, it may be desired to tailor less to use a character set other than the ones
       definable by LESSCHARSET.  In this case, the environment variable LESSCHARDEF can be  used
       to  define  a  character  set.	It  should be set to a string where each character in the
       string represents one character in the character set.  The character "."  is  used  for	a
       normal  character,  "c" for control, and "b" for binary.  A decimal number may be used for
       repetition.  For example, "bccc4b." would mean character 0 is binary, 1, 2 and 3 are  con-
       trol,  4, 5, 6 and 7 are binary, and 8 is normal.  All characters after the last are taken
       to be the same as the last, so characters 9 through 255 would  be  normal.   (This  is  an
       example, and does not necessarily represent any real character set.)

       This table shows the value of LESSCHARDEF which is equivalent to each of the possible val-
       ues for LESSCHARSET:

	    ascii     8bcccbcc18b95.b
	    dos       8bcccbcc12bc5b95.b.
	    ebcdic    5bc6bcc7bcc41b.9b7.9b5.b..8b6.10b6.b9.7b
		      9.8b8.17b3.3b9.7b9.8b8.6b10.b.b.b.
	    IBM-1047  4cbcbc3b9cbccbccbb4c6bcc5b3cbbc4bc4bccbc
		      191.b
	    iso8859   8bcccbcc18b95.33b.
	    koi8-r    8bcccbcc18b95.b128.
	    latin1    8bcccbcc18b95.33b.
	    next      8bcccbcc18b95.bb125.bb

       If neither LESSCHARSET nor LESSCHARDEF is set, but any of  the  strings	"UTF-8",  "UTF8",
       "utf-8" or "utf8" is found in the LC_ALL, LC_CTYPE or LANG environment variables, then the
       default character set is utf-8.

       If that string is not found, but your system supports the setlocale interface,  less  will
       use setlocale to determine the character set.  setlocale is controlled by setting the LANG
       or LC_CTYPE environment variables.

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

       Control	and binary characters are displayed in standout (reverse video).  Each such char-
       acter is displayed in caret notation if possible (e.g. ^A for control-A).  Caret  notation
       is  used  only  if inverting the 0100 bit results in a normal printable character.  Other-
       wise, the character is displayed as a hex number in angle brackets.  This  format  can  be
       changed	by  setting the LESSBINFMT environment variable.  LESSBINFMT may begin with a "*"
       and one character to select the display attribute: "*k" is blinking, "*d" is bold, "*u" is
       underlined,  "*s"  is  standout,  and "*n" is normal.  If LESSBINFMT does not begin with a
       "*", normal attribute is assumed.  The remainder of  LESSBINFMT	is  a  string  which  may
       include one printf-style escape sequence (a % followed by x, X, o, d, etc.).  For example,
       if LESSBINFMT is "*u[%x]", binary characters are displayed in underlined hexadecimal  sur-
       rounded	by  brackets.  The default if no LESSBINFMT is specified is "*s<%02X>".  Warning:
       the result of expanding the character via LESSBINFMT must be less than 31 characters.

       When the character set is utf-8, the LESSUTFBINFMT environment variable acts similarly  to
       LESSBINFMT  but	it  applies to Unicode code points that were successfully decoded but are
       unsuitable for display (e.g., unassigned code points).  Its default value is  "<U+%04lX>".
       Note  that  LESSUTFBINFMT  and  LESSBINFMT share their display attribute setting ("*x") so
       specifying one will affect both; LESSUTFBINFMT is read after LESSBINFMT so its setting, if
       any,  will  have  priority.   Problematic  octets  in  a UTF-8 file (octets of a truncated
       sequence, octets of a complete but non-shortest form sequence, illegal octets,  and  stray
       trailing  octets) are displayed individually using LESSBINFMT so as to facilitate diagnos-
       tic of how the UTF-8 file is ill-formed.

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

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

       %bX    Replaced	by  the  byte offset into the current input file.  The b is followed by a
	      single character (shown as X above) which specifies the line whose byte  offset  is
	      to be used.  If the character is a "t", the byte offset of the top line in the dis-
	      play is used, an "m" means use the middle line, a "b" means use the bottom line,	a
	      "B" means use the line just after the bottom line, and a "j" means use the "target"
	      line, as specified by the -j option.

       %B     Replaced by the size of the current input file.

       %c     Replaced by the column number of the text appearing in  the  first  column  of  the
	      screen.

       %dX    Replaced	by  the  page number of a line in the input file.  The line to be used is
	      determined by the X, as with the %b option.

       %D     Replaced by the number of pages in the input file, or equivalently, the page number
	      of the last line in the input file.

       %E     Replaced	by  the  name of the editor (from the VISUAL environment variable, or the
	      EDITOR environment variable if VISUAL is not defined).  See the discussion  of  the
	      LESSEDIT feature below.

       %f     Replaced by the name of the current input file.

       %F     Replaced by the last component of the name of the current input file.

       %i     Replaced by the index of the current file in the list of input files.

       %lX    Replaced	by  the  line number of a line in the input file.  The line to be used is
	      determined by the X, as with the %b option.

       %L     Replaced by the line number of the last line in the input file.

       %m     Replaced by the total number of input files.

       %pX    Replaced by the percent into the current input file, based on  byte  offsets.   The
	      line used is determined by the X as with the %b option.

       %PX    Replaced	by  the  percent into the current input file, based on line numbers.  The
	      line used is determined by the X as with the %b option.

       %s     Same as %B.

       %t     Causes any trailing spaces to be removed.  Usually used at the end of  the  string,
	      but may appear anywhere.

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

       If any item is unknown (for example, the file size if input is a pipe), a question mark is
       printed instead.

       The format of the prompt string can be changed depending on certain conditions.	 A  ques-
       tion  mark  followed  by  a single character acts like an "IF": depending on the following
       character, a condition is evaluated.  If the condition is true, any  characters	following
       the question mark and condition character, up to a period, are included in the prompt.  If
       the condition is false, such characters are not included.  A colon appearing  between  the
       question  mark  and  the period can be used to establish an "ELSE": any characters between
       the colon and the period are included in the string if and only if  the	IF  condition  is
       false.  Condition characters (which follow a question mark) may be:

       ?a     True if any characters have been included in the prompt so far.

       ?bX    True if the byte offset of the specified line is known.

       ?B     True if the size of current input file is known.

       ?c     True if the text is horizontally shifted (%c is not zero).

       ?dX    True if the page number of the specified line is known.

       ?e     True if at end-of-file.

       ?f     True if there is an input filename (that is, if input is not a pipe).

       ?lX    True if the line number of the specified line is known.

       ?L     True if the line number of the last line in the file is known.

       ?m     True if there is more than one input file.

       ?n     True if this is the first prompt in a new input file.

       ?pX    True  if	the  percent  into  the current input file, based on byte offsets, of the
	      specified line is known.

       ?PX    True if the percent into the current input file, based  on  line	numbers,  of  the
	      specified line is known.

       ?s     Same as "?B".

       ?x     True  if	there is a next input file (that is, if the current input file is not the
	      last one).

       Any characters other than the special ones (question mark,  colon,  period,  percent,  and
       backslash)  become  literally  part  of	the prompt.  Any of the special characters may be
       included in the prompt literally by preceding it with a backslash.

       Some examples:

       ?f%f:Standard input.

       This prompt prints the filename, if known; otherwise the string "Standard input".

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

       This prompt would print the filename, if known.	The filename is followed by the line num-
       ber, if known, otherwise the percent if known, otherwise the byte offset if known.  Other-
       wise, a dash is printed.  Notice how each question mark has a matching period, and how the
       % after the %pt is included literally by escaping it with a backslash.

       ?n?f%f .?m(file %i of %m) ..?e(END) ?x- Next\: %x..%t

       This prints the filename if this is the first prompt in a file, followed by the "file N of
       N" message if there is more than one input file.  Then, if  we  are  at	end-of-file,  the
       string  "(END)"	is  printed  followed  by  the	name  of  the next file, if there is one.
       Finally, any trailing spaces are truncated.  This is the default prompt.   For  reference,
       here  are the defaults for the other two prompts (-m and -M respectively).  Each is broken
       into two lines here for readability only.

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

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

       And here is the default message produced by the = command:

       ?f%f .?m(file %i of %m) .?ltlines %lt-%lb?L/%L. .
	    byte %bB?s/%s. ?e(END) :?pB%pB\%..%t

       The prompt expansion features are also used for another purpose: if an  environment  vari-
       able  LESSEDIT  is defined, it is used as the command to be executed when the v command is
       invoked.  The LESSEDIT string is expanded in the same way  as  the  prompt  strings.   The
       default value for LESSEDIT is:

	    %E ?lm+%lm. %f

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

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

	      !      the shell command

	      |      the pipe command

	      :e     the examine command.

	      v      the editing command

	      s  -o  log files

	      -k     use of lesskey files

	      -t     use of tags files

		     metacharacters in filenames, such as *

		     filename completion (TAB, ^L)

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

COMPATIBILITY WITH MORE
       If  the	environment variable LESS_IS_MORE is set to 1, or if the program is invoked via a
       file link named "more", less behaves (mostly) in conformance with the POSIX "more" command
       specification.  In this mode, less behaves differently in these ways:

       The  -e	option works differently.  If the -e option is not set, less behaves as if the -E
       option were set.  If the -e option is set, less behaves as if the -e and -F  options  were
       set.

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

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

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

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

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

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

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

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

       HOMEDRIVE, HOMEPATH
	      Concatenation of the HOMEDRIVE and HOMEPATH environment variables is  the  name  of
	      the user's home directory if the HOME variable is not set (only in the Windows ver-
	      sion).

       INIT   Name of the user's init directory (used to find a lesskey file on OS/2 systems).

       LANG   Language for determining the character set.

       LC_CTYPE
	      Language for determining the character set.

       LESS   Options which are passed to less automatically.

       LESSANSIENDCHARS
	      Characters which may end an ANSI color escape sequence (default "m").

       LESSANSIMIDCHARS
	      Characters which may appear between the ESC character and the end character  in  an
	      ANSI color escape sequence (default "0123456789;[?!"'#%()*+ ".

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

       LESSCHARDEF
	      Defines a character set.

       LESSCHARSET
	      Selects a predefined character set.

       LESSCLOSE
	      Command line to invoke the (optional) input-postprocessor.

       LESSECHO
	      Name  of the lessecho program (default "lessecho").  The lessecho program is needed
	      to expand metacharacters, such as * and ?, in filenames on Unix systems.

       LESSEDIT
	      Editor prototype string (used for the v command).  See discussion under PROMPTS.

       LESSGLOBALTAGS
	      Name of the command used by the -t option to find global tags.  Normally should  be
	      set to "global" if your system has the global (1) command.  If not set, global tags
	      are not used.

       LESSHISTFILE
	      Name of the history file used  to  remember  search  commands  and  shell  commands
	      between  invocations  of less.  If set to "-" or "/dev/null", a history file is not
	      used.  The default is "$HOME/.lesshst" on Unix systems, "$HOME/_lesshst" on DOS and
	      Windows systems, or "$HOME/lesshst.ini" or "$INIT/lesshst.ini" on OS/2 systems.

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

       LESSKEY
	      Name of the default   lesskey(1)  file.

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

       LESSMETACHARS
	      List of characters which are considered "metacharacters" by the shell.

       LESSMETAESCAPE
	      Prefix  which  less  will  add  before  each metacharacter in a command sent to the
	      shell.  If LESSMETAESCAPE is an empty string,  commands  containing  metacharacters
	      will not be passed to the shell.

       LESSOPEN
	      Command line to invoke the (optional) input-preprocessor.

       LESSSECURE
	      Runs less in "secure" mode.  See discussion under SECURITY.

       LESSSEPARATOR
	      String to be appended to a directory name in filename completion.

       LESSUTFBINFMT
	      Format for displaying non-printable Unicode code points.

       LESS_IS_MORE
	      Emulate the more (1) command.

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

       PATH   User's search path (used to find a lesskey file on MS-DOS and OS/2 systems).

       SHELL  The shell used to execute the ! command, as well as to expand filenames.

       TERM   The type of terminal on which less is being run.

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

SEE ALSO
         lesskey(1) 

COPYRIGHT
       Copyright (C) 1984-2011	Mark Nudelman

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

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

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

				     Version 444: 09 Jun 2011				    LESS(1)
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