Provided by: less_444-1ubuntu1_i386 bug

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  behavior  is
              similar to the "tail -f" command.)

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

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

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

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

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

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

       ESC-^B Followed  by  two  characters,  acts  like  },  but uses the two
              characters  as  open  and  close  brackets,  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.
              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 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
                     current screen, but don't move to the first  match  (KEEP
                     current position).

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

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

              Certain characters are special as in the / command:

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

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

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

              ^K     As in forward searches.

              ^R     As in forward searches.

       ESC-/pattern
              Same as "/*".

       ESC-?pattern
              Same as "?*".

       n      Repeat previous  search,  for  N-th  line  containing  the  last
              pattern.   If the previous search was modified by ^N, the search
              is made for the N-th line NOT containing the  pattern.   If  the
              previous  search was 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
              crossing file boundaries.

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

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

              Certain characters are special as in the / command:

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

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

       :e [filename]
              Examine a new file.  If the filename is missing,  the  "current"
              file  (see  the :n and :p commands below) from the list of files
              in the command line is re-examined.  A percent sign (%)  in  the
              filename  is  replaced by the name of the current file.  A pound
              sign (#) is replaced by the  name  of  the  previously  examined
              file.    However,  two  consecutive  percent  signs  are  simply
              replaced with a single percent sign.  This allows you to enter a
              filename  that  contains a percent sign in the name.  Similarly,
              two 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 letter.

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

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

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

       __     (Double underscore.)  Like the _ (underscore) command, but takes
              a long option name rather than a single option letter.  You must
              press 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 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
              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 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
              indicate beginning or end of file respectively.  If <m> is .  or
              newline, the current screen is piped.

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

OPTIONS

       Command line options are described below.  Most options may be  changed
       while less is running, via the "-" 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  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
              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 kilobytes (1024 bytes).   By  default  64K  of
              buffer  space  is used for each file (unless the file is a pipe;
              see the -B option).  The -b  option  specifies  instead  that  n
              kilobytes of buffer space should be used for each file.  If n is
              -1, buffer space is unlimited; that is, the entire file  can  be
              read into memory.

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

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

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

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

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

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

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

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

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

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

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

       -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  (usually  ^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  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
              occurrence of pattern in the file.

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

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

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

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

       -R or --RAW-CONTROL-CHARS
              Like  -r,  but  only ANSI "color" escape sequences are output in
              "raw" form.  Unlike -r,  the  screen  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 characters which can appear.

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

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

       -ttag or --tag=tag
              The -t option, followed immediately by a TAG, will edit the file
              containing that tag.  For this to work, tag information must  be
              available;  for  example,  there  may  be  a file in the current
              directory called "tags", which was previously built by ctags (1)
              or   an   equivalent   command.   If  the  environment  variable
              LESSGLOBALTAGS is set, it is taken to be the name of  a  command
              compatible with global (1), and that 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
              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 command.
              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   something  unnecessary,  like
              clearing the screen.

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

       -[z]n or --window=n
              Changes the default scrolling  window  size  to  n  lines.   The
              default is one screenful.  The z and w 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
              negative, it indicates n lines  less  than  the  current  screen
              size.   For  example,  if  the screen is 24 lines, -z-4 sets the
              scrolling window to 20 lines.  If the screen is  resized  to  40
              lines, the scrolling window automatically changes to 36 lines.

       -"cc or --quotes=cc
              Changes  the  filename quoting character.  This may be necessary
              if you are trying to name a file which contains both spaces  and
              quote  characters.  Followed by a single character, this changes
              the quote character to that character.  Filenames  containing  a
              space should then be surrounded by that character rather than by
              double quotes.  Followed by two  characters,  changes  the  open
              quote  to the first 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
              specified is zero, it sets the default number  of  positions  to
              one  half  of  the screen width.  Alternately, the number may be
              specified as a fraction of the width  of  the  screen,  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 terminal.  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  previously  may  also  be  used to set (or change) an
              initial command for every file.

LINE EDITING

       When entering command line at the bottom of the screen (for example,  a
       filename  for  the  :e  command,  or the 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" character, either ^V or
       ^A.  A backslash itself may also be entered literally by  entering  two
       backslashes.

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

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

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

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

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

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

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

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

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

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

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

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

       TAB    Complete the partial filename to the left of the cursor.  If  it
              matches  more than one filename, the first match is entered into
              the command line.  Repeated  TABs  will  cycle  thru  the  other
              matching 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  "$HOME/.less".  On MS-DOS and Windows systems, less looks
       for a lesskey file called "$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:\_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 preprocessor is not called when viewing standard input.   To  set
       up  an  input  preprocessor, set the LESSOPEN environment variable to a
       command line which will invoke your input preprocessor.   This  command
       line  should  include  one occurrence of the string "%s", which will be
       replaced by  the  filename  when  the  input  preprocessor  command  is
       invoked.

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

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

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

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

       To  use these scripts, put them both where they can be executed and set
       LESSOPEN="lessopen.sh %s",  and  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  standard output, then there is no
       replacement file and less uses the original file, as normal.  To use an
       input  pipe,  make  the  first  character  in  the LESSOPEN environment
       variable a vertical bar (|) to signify that the input  preprocessor  is
       an input pipe.

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

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

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

       For  compatibility  with  previous  versions   of   less,   the   input
       preprocessor  or  pipe  is  not used if less is viewing standard input.
       However, if the first character of LESSOPEN is a dash  (-),  the  input
       preprocessor is used on standard input as well as other files.  In this
       case, the dash is  not  considered  to  be  part  of  the  preprocessor
       command.   If standard input is being viewed, the input preprocessor is
       passed a file name consisting of a  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 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.
              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 control, 4, 5, 6 and 7
       are binary, and 8 is normal.  All characters after the last  are  taken
       to  be  the  same  as  the  last,  so characters 9 through 255 would be
       normal.  (This is an example, and does not  necessarily  represent  any
       real character set.)

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

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

       If neither LESSCHARSET nor LESSCHARDEF is set, but any of  the  strings
       "UTF-8",  "UTF8", "utf-8" or "utf8" is found in the LC_ALL, LC_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 character is displayed in caret notation if possible
       (e.g. ^A for control-A).  Caret notation is used only if inverting  the
       0100  bit  results  in  a  normal  printable character.  Otherwise, the
       character is displayed as a hex number in angle 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<%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 diagnostic of how the UTF-8 file is ill-formed.

PROMPTS

       The  -P option allows you to tailor the prompt to your preference.  The
       string given to the -P option replaces  the  specified  prompt  string.
       Certain characters in the string are interpreted specially.  The prompt
       mechanism  is  rather  complicated  to  provide  flexibility,  but  the
       ordinary   user   need  not  understand  the  details  of  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
              display  is  used, an "m" means use the middle line, a "b" means
              use the bottom line, a "B" means use the  line  just  after  the
              bottom line, and a "j" means use the "target" line, as specified
              by the -j option.

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

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

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

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

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

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

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

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

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

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

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

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

       ?e     True if at end-of-file.

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

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

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

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

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

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

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

       ?s     Same as "?B".

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

       Any  characters  other  than  the  special  ones (question mark, colon,
       period, percent, and backslash) become 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 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,
       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  variable LESSEDIT is defined, it is used as the command to
       be executed when the v command is  invoked.   The  LESSEDIT  string  is
       expanded  in the same way as the prompt strings.  The default value for
       LESSEDIT is:

            %E ?lm+%lm. %f

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

SECURITY

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

              !      the shell command

              |      the pipe command

              :e     the examine command.

              v      the editing command

              s  -o  log files

              -k     use of lesskey files

              -t     use of tags files

                     metacharacters in filenames, such as *

                     filename completion (TAB, ^L)

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

COMPATIBILITY WITH MORE

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

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

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

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

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

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

ENVIRONMENT VARIABLES

       Environment variables may be specified either in the system environment
       as  usual,  or  in  a  lesskey  (1) file.  If environment variables are
       defined in more than one place, variables defined in  a  local  lesskey
       file  take 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
              variables  is  the name of the user's home directory if the HOME
              variable is not set (only in the Windows version).

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

       LANG   Language for determining the character set.

       LC_CTYPE
              Language for determining the character set.

       LESS   Options which are passed to less automatically.

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

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

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

       LESSCHARDEF
              Defines a character set.

       LESSCHARSET
              Selects a predefined character set.

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

       LESSECHO
              Name of the lessecho program (default "lessecho").  The lessecho
              program  is needed to expand 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 precedence
              over the LINES and COLUMNS environment variables.)

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

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

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

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

SEE ALSO

       lesskey(1)

COPYRIGHT

       Copyright (C) 1984-2011  Mark Nudelman

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

       less is distributed in the hope that it will be useful, but WITHOUT ANY
       WARRANTY;  without  even  the  implied  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)