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LESS(1)                                                                LESS(1)



NAME
       less(1,3) - opposite of more

SYNOPSIS
       less(1,3) -?
       less(1,3) --help
       less(1,3) -V
       less(1,3) --version
       less(1,3) [-[+]aBcCdeEfFgGiIJLmMnNqQrRsSuUVwWX~]
            [-b space] [-h lines] [-j line] [-k keyfile]
            [-{oO} logfile] [-p pattern] [-P prompt] [-t tag]
            [-T tagsfile] [-x tab,...] [-y lines] [-[z] lines]
            [-# shift] [+[+]cmd] [--] [filename]...
       (See  the  OPTIONS section for alternate option syntax with long option
       names.)


DESCRIPTION
       Less is a program similar to more (1), but which allows backward  move-
       ment in(1,8) the file(1,n) as well as forward movement.  Also, less(1,3) does not have
       to read(2,n,1 builtins) the entire input file(1,n) 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(1,8) the descriptions below.  The number is used
       by some commands, as indicated.


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

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

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

       z      Like  SPACE,  but  if(3,n)  N is specified, it becomes the new window
              size.

       ESC-SPACE
              Like SPACE, but scrolls a full screenful,  even  if(3,n)  it  reaches
              end-of-file in(1,8) the process.

       RETURN or ^N or e or ^E or j or ^J
              Scroll  forward N lines, default 1.  The entire N lines are dis-
              played, even if(3,n) 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(3,n) N is specified, it  becomes  the  new  window
              size.

       y or ^Y or ^P or k or ^K
              Scroll backward N lines, default 1.  The entire N lines are dis-
              played, even if(3,n) N is more than the screen size.   Warning:  some
              systems use ^Y as a special job control character.

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

       ESC-) or RIGHTARROW
              Scroll  horizontally right N characters, default half the screen
              width (see the -# option).  If  a  number  N  is  specified,  it
              becomes  the  default  for  future RIGHTARROW and LEFTARROW com-
              mands.  While the text is scrolled, it acts  as  though  the  -S
              option (chop lines) were in(1,8) effect.

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

       r or ^R or ^L
              Repaint the screen.

       R      Repaint the screen, discarding any buffered  input.   Useful  if(3,n)
              the file(1,n) is changing while it is being viewed.

       F      Scroll  forward, and keep trying to read(2,n,1 builtins) when the end of file(1,n) 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(1,n)
              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(1,8) the file(1,n), default 1 (beginning of file(1,n)).  (Warn-
              ing: this may be slow if(3,n) N is large.)

       G or > or ESC->
              Go to line N in(1,8) the file(1,n), default the end of the  file.   (Warn-
              ing:  this  may  be slow if(3,n) N is large, or if(3,n) N is not specified
              and standard input, rather than a file(1,n), is being read.)

       p or % Go to a position N percent into the file.  N should be between 0
              and 100.

       {      If a left curly bracket appears in(1,8) 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(1,8) the bottom line displayed on
              the  screen,  the  }  command will go to the matching left curly
              bracket.  The matching left curly bracket is positioned  on  the
              top  line  of the screen.  If there is more than one right curly
              bracket on the top line, a number N may be used to  specify  the
              N-th bracket on the line.

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

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

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

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

       ESC-^F Followed  by two characters, acts like {, but uses the two char-
              acters as open(2,3,n) and close(2,7,n) brackets, respectively.   For  example,
              "ESC  ^F < >" could be used to go forward to the > which matches
              the < in(1,8) the top displayed line.

       ESC-^B Followed by two characters, acts like }, but uses the two  char-
              acters  as  open(2,3,n) and close(2,7,n) brackets, respectively.  For example,
              "ESC ^B < >" could be used to go backward to the < which matches
              the > in(1,8) the bottom displayed line.

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

       '      (Single quote.)  Followed by any lowercase  letter,  returns  to
              the position which was previously marked with that letter.  Fol-
              lowed by another single quote, returns to the position at  which
              the last "large" movement command was executed.  Followed by a ^
              or $, jumps to the beginning or end of  the  file(1,n)  respectively.
              Marks  are  preserved when a new file(1,n) is examined, so the ' com-
              mand can be used to switch(1,n) between input files.

       ^X^X   Same as single quote.

       /pattern
              Search forward in(1,8) the file(1,n) for the N-th line containing the pat-
              tern.  N defaults to 1.  The pattern is a regular expression, as
              recognized by ed.  The search starts at  the  second  line  dis-
              played (but see the -a and -j options, which change this).

              Certain  characters  are  special if(3,n) 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(3,n) the search reaches
                     the END of the current file(1,n) without finding a match,  the
                     search  continues  in(1,8)  the  next file(1,n) in(1,8) the command line
                     list.

              ^F or @
                     Begin the search at the first line of the FIRST  file(1,n)  in(1,8)
                     the  command  line  list, regardless of what is currently
                     displayed on the screen or the settings of the -a  or  -j
                     options.

              ^K     Highlight  any text which matches the pattern on the cur-
                     rent screen, but don't move(3x,7,3x curs_move) to the first match (KEEP cur-
                     rent position).

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

       ?pattern
              Search backward in(1,8) the file(1,n) 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(1,8) the / command:

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

              ^E or *
                     Search multiple files.  That is, if(3,n)  the  search  reaches
                     the  beginning  of  the  current  file(1,n)  without finding a
                     match, the search continues in(1,8) the previous file(1,n)  in(1,8)  the
                     command line list.

              ^F or @
                     Begin the search at the last line of the last file(1,n) in(1,8) the
                     command line list, regardless of what is  currently  dis-
                     played  on  the  screen  or  the settings of the -a or -j
                     options.

              ^K     As in(1,8) forward searches.

              ^R     As in(1,8) forward searches.

       ESC-/pattern
              Same as "/*".

       ESC-?pattern
              Same as "?*".

       n      Repeat previous search, for N-th line containing the  last  pat-
              tern.   If the previous search was modified by ^N, the search is
              made for the N-th line NOT containing the pattern.  If the  pre-
              vious  search  was  modified  by ^E, the search continues in(1,8) the
              next (or previous) file(1,n) if(3,n) not satisfied in(1,8)  the  current  file.
              If  the  previous  search was modified by ^R, the search is done
              without using regular expressions.  There is no  effect  if(3,n)  the
              previous search was modified by ^F or ^K.

       N      Repeat previous search, but in(1,8) the reverse direction.

       ESC-n  Repeat  previous  search,  but  crossing  file(1,n)  boundaries.  The
              effect is as if(3,n) the previous search were modified by *.

       ESC-N  Repeat previous search, but in(1,8) the reverse direction and  cross-
              ing file(1,n) 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(1,8)
              that case search commands do not turn highlighting back on.)

       :e [filename]
              Examine a new file.  If the filename is missing,  the  "current"
              file(1,n)  (see  the :n and :p commands below) from the list of files
              in(1,8) the command line is re-examined.  A percent sign (%)  in(1,8)  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(1,8) 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(1,8) double quotes (also see the -" option).

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

       :n     Examine the next file(1,n) (from the list of files given in(1,8) the  com-
              mand  line).   If a number N is specified, the N-th next file(1,n) is
              examined.

       :p     Examine the previous file(1,n) in(1,8) the command line list.  If a number
              N is specified, the N-th previous file(1,n) is examined.

       :x     Examine  the first file(1,n) in(1,8) the command line list.  If a number N
              is specified, the N-th file(1,n) in(1,8) the list is examined.

       :d     Remove the current file(1,n) from the list of files.

       t      Go to the next tag, if(3,n) 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(3,n) there were more than one matches for
              the current tag.

       = or ^G or :f
              Prints some information about the file(1,n) 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(1,n),  the  number  of  lines in(1,8) the file(1,n) and the percent of the
              file(1,n) 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(3,n) value (such as -P
              or -t), a new value may be entered after the option letter.   If
              no  new  value is entered, a message describing the current set-
              ting is printed and nothing is changed.

       --     Like the - command, but takes a long option  name  (see  OPTIONS
              below)  rather  than  a  single  option  letter.  You must press
              RETURN after typing the option name.  A ^P immediately after the
              second  dash suppresses printing of a message describing the new
              setting, as in(1,8) the - command.

       -+     Followed by one of the command line  option  letters  this  will
              reset(1,7,1 tput)  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(1,7,1 tput) the option to the "opposite" of its  default  setting  and
              print  a message describing the new setting.  This does not work
              for numeric or string-valued options.

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

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

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

       +cmd   Causes  the specified cmd to be executed each time(1,2,n) a new file(1,n) is
              examined.  For example, +G causes less(1,3) to initially display each
              file(1,n) starting at the end rather than the beginning.

       V      Prints the version(1,3,5) number of less(1,3) 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(1,n)  being  viewed.   The
              editor is taken from the environment variable VISUAL if(3,n) defined,
              or EDITOR if(3,n) VISUAL is not defined, or defaults to "vi" if(3,n)  nei-
              ther  VISUAL  nor EDITOR is defined.  See also the discussion of
              LESSEDIT under the section on PROMPTS below.

       ! shell-command
              Invokes a shell to run the shell-command given.  A percent  sign
              (%)  in(1,8) the command is replaced by the name of the current file.
              A pound sign (#) is replaced by the name of the previously exam-
              ined  file.   "!!"  repeats the last shell command.  "!" with no
              shell command simply invokes a  shell.   On  Unix  systems,  the
              shell  is taken from the environment variable SHELL, or defaults
              to "sh".  On MS-DOS and OS/2 systems, the shell  is  the  normal
              command processor.

       | <m> shell-command
              <m>  represents  any  mark letter.  Pipes a section of the input
              file(1,n) to the given shell command.  The section of the file(1,n) to  be
              piped  is  between  the first line on the current screen and the
              position marked by the letter.  <m> may also be ^ or $ to  indi-
              cate beginning or end of file(1,n) respectively.  If <m> is . or new-
              line, the current screen is piped.

       s filename
              Save the input to a file.  This only works if(3,n)  the  input  is  a
              pipe(2,8), not an ordinary file.


OPTIONS
       Command  line options are described below.  Most options may be changed
       while less(1,3) is running, via the "-" command.

       Most options may be given in(1,8) 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(1,8) uppercase, such as --QUIT-AT-EOF, as distinct
       from --quit-at-eof.  Such option names need only have their first  let-
       ter  capitalized; the remainder of the name may be in(1,8) either case.  For
       example, --Quit-at-eof is equivalent to --QUIT-AT-EOF.

       Options are also taken from the environment variable "LESS".  For exam-
       ple, to avoid typing "less(1,3) -options ..." each time(1,2,n) less(1,3) is invoked, you
       might tell csh:

       setenv LESS "-options"

       or if(3,n) you use sh:

       LESS="-options"; export LESS

       On MS-DOS, you don't need the quotes, but you should replace  any  per-
       cent signs in(1,8) the options string(3,n) 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(1,8)  the LESS variable, it can be reset(1,7,1 tput) 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(3,n), a dollar  sign
       ($)  must be used to signal(2,7) the end of the string.  For example, to set(7,n,1 builtins)
       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(1,3)
              (the same as the h  command).   (Depending  on  how  your  shell
              interprets  the  question mark, it may be necessary to quote the
              question mark, thus: "-\?".)

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

       -bn or --buffers=n
              Specifies  the  amount  of  buffer  space less(1,3) will use for each
              file(1,n), in(1,8) units(1,7) of kilobytes (1024 bytes).   By  default  64K  of
              buffer  space  is used for each file(1,n) (unless the file(1,n) is a pipe(2,8);
              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(1,n) is  read(2,n,1 builtins)
              into memory.

       -B or --auto-buffers
              By default, when data is read(2,n,1 builtins) from a pipe(2,8), buffers are allocated
              automatically as needed.  If a large amount of data is read(2,n,1 builtins) from
              the  pipe(2,8),  this  can cause a large amount of memory to be allo-
              cated.  The -B option  disables  this  automatic  allocation  of
              buffers  for  pipes,  so  that  only 64K (or the amount of space
              specified by the -b option) is used for the pipe.  Warning:  use
              of  -B  can  result  in(1,8)  erroneous  display, since only the most
              recently viewed part of the file(1,n) is kept in(1,8) memory; any  earlier
              data is lost.

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

       -C or --CLEAR-SCREEN
              The -C option is like -c, but the screen is cleared before it is
              repainted.

       -d or --dumb
              The -d option suppresses the error(8,n) message normally displayed if(3,n)
              the  terminal is dumb; that is, lacks some important capability,
              such as the ability to clear(1,3x,3x clrtobot) the screen or scroll backward.  The
              -d  option  does  not otherwise change the behavior of less(1,3) on a
              dumb terminal.

       -Dxcolor or --color=xcolor
              [MS-DOS only] Sets the color of the text displayed.  x is a sin-
              gle  character  which  selects  the  type of text whose color is
              being set: n=normal, s=standout, d=bold, u=underlined,  k=blink.
              color  is  a  pair  of numbers separated by a period.  The first
              number selects the foreground color and the second  selects  the
              background  color of the text.  A single number N is the same as
              N.0.

       -e or --quit-at-eof
              Causes less(1,3) to automatically exit(3,n,1 builtins) the  second  time(1,2,n)  it  reaches
              end-of-file.   By  default, the only way to exit(3,n,1 builtins) less(1,3) is via the
              "q" command.

       -E or --QUIT-AT-EOF
              Causes less(1,3) to automatically exit(3,n,1 builtins) the first time(1,2,n) it reaches end-
              of-file.

       -f or --force
              Forces non-regular files to be opened.  (A non-regular file(1,n) is a
              directory or a device special file.)  Also suppresses the  warn-
              ing message when a binary file(1,n) is opened.  By default, less(1,3) will
              refuse to open(2,3,n) non-regular files.

       -F or --quit-if-one-screen
              Causes less(1,3) to automatically exit(3,n,1 builtins) if(3,n) the entire file(1,n) can be dis-
              played on the first screen.

       -g or --hilite-search
              Normally,  less(1,3)  will highlight ALL strings which match the last
              search command.  The -g option changes this  behavior  to  high-
              light  only  the  particular  string(3,n) which was found by the last
              search command.  This can cause less(1,3) 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(1,8) 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(3,n) any  upper-
              case  letters appear in(1,8) the search pattern; in(1,8) other words, if(3,n) a
              pattern contains uppercase letters, then that  search  does  not
              ignore case.

       -I or --IGNORE-CASE
              Like  -i,  but searches ignore case even if(3,n) the pattern contains
              uppercase letters.

       -jn or --jump-target=n
              Specifies a line on the screen where the "target" line is to  be
              positioned.   A  target line is the object of a text search, tag
              search, jump to a line number, jump to  a  file(1,n)  percentage,  or
              jump  to  a  marked position.  The screen line is specified by a
              number: the top line on the screen is 1, the next is 2,  and  so
              on.   The  number  may be negative to specify a line relative to
              the bottom of the screen: the bottom line on the screen  is  -1,
              the  second to the bottom is -2, and so on.  If the -j option is
              used, searches begin at the line immediately  after  the  target
              line.   For  example,  if(3,n)  "-j4" is used, the target line is the
              fourth line on the screen, so searches begin at the  fifth  line
              on the screen.

       -J or --status-column
              Displays  a  status  column at the left edge of the screen.  The
              status column shows the lines that matched the  current  search.
              The  status  column  is  also  used if(3,n) the -w or -W option is in(1,8)
              effect.

       -kfilename or --lesskey-file=filename
              Causes less(1,3) to open(2,3,n) and interpret the named(5,8) file(1,n)  as  a  lesskey
              (1) file.  Multiple -k options may be specified.  If the LESSKEY
              or LESSKEY_SYSTEM environment variable is set(7,n,1 builtins), or if(3,n)  a  lesskey
              file(1,n) is found in(1,8) a standard place (see KEY BINDINGS), it is also
              used as a lesskey file.

       -L or --no-lessopen
              Ignore the LESSOPEN environment variable  (see  the  INPUT  PRE-
              PROCESSOR  section  below).   This option can be set(7,n,1 builtins) from within
              less(1,3), but it will apply only to files opened  subsequently,  not
              to the file(1,n) which is currently open.

       -m or --long-prompt
              Causes  less(1,3)  to  prompt verbosely (like more), with the percent
              into the file.  By default, less(1,3) prompts with a colon.

       -M or --LONG-PROMPT
              Causes less(1,3) to prompt even more verbosely than more.

       -n or --line-numbers
              Suppresses line numbers.  The default (to use line numbers)  may
              cause  less(1,3)  to run more slowly in(1,8) 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(1,8) the verbose prompt and in(1,8) the =
              command,  and the v command will pass the current line number to
              the editor (see also  the  discussion  of  LESSEDIT  in(1,8)  PROMPTS
              below).

       -N or --LINE-NUMBERS
              Causes  a  line  number to be displayed at the beginning of each
              line in(1,8) the display.

       -ofilename or --log-file=filename
              Causes less(1,3) to copy its input to the named(5,8) file(1,n) as it  is  being
              viewed.  This applies only when the input file(1,n) is a pipe(2,8), not an
              ordinary file.  If the file(1,n) already exists, less(1,3)  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(1,n)
              without asking for confirmation.

              If no log file(1,n) has been specified, the -o and -O options can  be
              used  from  within  less(1,3)  to specify a log file.  Without a file(1,n)
              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(1,3) to start at the  first  occur-
              rence of pattern in(1,8) 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(1,8) the LESS envi-
              ronment variable, rather than being typed in(1,8) with each less(1,3) com-
              mand.  Such an option must either be the last option in(1,8) the LESS
              variable,  or be terminated by a dollar sign.  -Ps followed by a
              string(3,n) 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(1,8) 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(3,n) an attempt is made to scroll past the end of the file(1,n) 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(1,8) 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(3x,7,8,3x cbreak)" 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(1,3) cannot keep track of the actual
              appearance  of  the screen (since this depends on how the screen
              responds to each type of control character).  Thus, various dis-
              play  problems may result, such as long lines being split(1,n) in(1,8) the
              wrong place.

       -R or --RAW-CONTROL-CHARS
              Like -r, but tries to keep track of the screen appearance  where
              possible.   This works only if(3,n) the input consists of normal text
              and possibly some  ANSI  "color"  escape  sequences,  which  are
              sequences of the form:

                   ESC [ ... m

              where  the "..." is zero or more characters other than "m".  For
              the purpose of keeping track of screen appearance,  all  control
              characters  and  all  ANSI color escape sequences are assumed to
              not move(3x,7,3x curs_move) the cursor.  You can make less(1,3)  think  that  characters
              other  than  "m"  can end ANSI color escape sequences by setting
              the environment variable LESSANSIENDCHARS to the list of charac-
              ters which can end a color escape sequence.

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

       -S or --chop-long-lines
              Causes lines longer than the screen width to be  chopped  rather
              than  folded.  That is, the portion of a long line that does not
              fit in(1,8) 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(1,n)
              containing that tag.  For this to work, tag information must  be
              available;  for  example,  there  may  be  a file(1,n) in(1,8) the current
              directory called "tags", which was previously built by ctags (1)
              or an equivalent command.  If the environment variable LESSGLOB-
              ALTAGS is set(7,n,1 builtins), it is taken to be the name of a command  compati-
              ble  with  global  (1), and that command is executed to find the
              tag.  (See http://www.gnu.org/software/global/global.html).  The
              -t  option  may  also be specified from within less(1,3) (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(1,n) to be used instead of "tags".

       -u or --underline-special
              Causes  backspaces  and carriage returns to be treated as print-
              able characters; that is, they are sent  to  the  terminal  when
              they appear in(1,8) 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(3,n)  neither  -u  nor -U is given, backspaces which
              appear adjacent to an  underscore  character  are  treated  spe-
              cially:  the  underlined  text is displayed using the terminal's
              hardware underlining capability.  Also, backspaces which  appear
              between  two  identical  characters  are  treated specially: the
              overstruck text is printed using the terminal's  hardware  bold-
              face  capability.   Other backspaces are deleted, along with the
              preceding character.  Carriage returns immediately followed by a
              newline  are  deleted.   other  carriage  returns are handled as
              specified by the -r option.  Text which is overstruck or  under-
              lined can be searched for if(3,n) neither -u nor -U is in(1,8) effect.

       -V or --version
              Displays the version(1,3,5) number of less.

       -w or --hilite-unread
              Temporarily  highlights  the  first  "new"  line after a forward
              movement of a full page.  The first "new" line is the line imme-
              diately  following  the  line  previously  at  the bottom of the
              screen.  Also highlights the target line after a g or p command.
              The  highlight is removed at the next command which causes move-
              ment.  The entire line is highlighted, unless the -J  option  is
              in(1,8)  effect, in(1,8) 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(7,n,1 builtins)
              at multiples of n.  If multiple values separated by  commas  are
              specified,  tab  stops are set(7,n,1 builtins) at those positions, and then con-
              tinue with the same spacing  as  the  last  two.   For  example,
              -x9,17  will  set(7,n,1 builtins)  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(3,n) the
              deinitialization string(3,n) does something unnecessary, like  clear-
              ing the screen.

       --no-keypad
              Disables  sending the keypad initialization and deinitialization
              strings to the terminal.  This is sometimes useful if(3,n) the keypad
              strings make the numeric keypad behave in(1,8) an undesirable manner.

       -yn or --max-forw-scroll=n
              Specifies a maximum number of lines to scroll forward.  If it is
              necessary  to  scroll  forward  more than n lines, the screen is
              repainted instead.  The -c or -C option may be used  to  repaint
              from  the top of the screen if(3,n) desired.  By default, any forward
              movement causes scrolling.

       -[z]n or --window=n
              Changes the default scrolling  window  size  to  n  lines.   The
              default is one screenful.  The z and w commands can also be used
              to change the window size.  The "z" may be omitted for  compati-
              bility  with  more.  If the number n is negative, it indicates n
              lines less(1,3) than the current screen size.  For  example,  if(3,n)  the
              screen  is 24 lines, -z-4 sets the scrolling window to 20 lines.
              If the screen is resized to 40 lines, the scrolling window auto-
              matically changes to 36 lines.

       -"cc or --quotes=cc
              Changes  the  filename quoting character.  This may be necessary
              if(3,n) you are trying to name a file(1,n) 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(2,3,n)
              quote  to the first character, and the close(2,7,n) quote to the second
              character.  Filenames containing a space should then be preceded
              by  the  open(2,3,n)  quote  character  and followed by the close(2,7,n) 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(1,n) are displayed as a single tilde
              (~).  This option causes lines after end of file(1,n) to be displayed
              as blank lines.

       -# or --shift
              Specifies the default number of positions to scroll horizontally
              in(1,8)  the RIGHTARROW and LEFTARROW commands.  If the number speci-
              fied is zero, it sets the default number  of  positions  to  one
              half of the screen width.

       --     A  command  line  argument of "--" marks the end of option argu-
              ments.  Any arguments following this are  interpreted  as  file-
              names.  This can be useful when viewing a file(1,n) 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(1,3) to start at the end of the file(1,n)  rather  than  the
              beginning,  and  +/xyz tells it to start at the first occurrence
              of "xyz" in(1,8) 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(1,n) being viewed, not just the first one.  The +  command
              described previously may also be used to set(7,n,1 builtins) (or change) an ini-
              tial command for every file.


LINE EDITING
       When entering command line at the bottom of the screen (for example,  a
       filename for the :e command, or the pattern for a search command), cer-
       tain keys can be used to manipulate the command  line.   Most  commands
       have  an alternate form in(1,8) [ brackets ] which can be used if(3,n) a key does
       not exist on a particular keyboard.  (The bracketed forms do  not  work
       in(1,8)  the MS-DOS version.)  Any of these special keys may be entered lit-
       erally by preceding it with the "literal" character, either ^V  or  ^A.
       A  backslash itself may also be entered literally by entering two back-
       slashes.

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

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

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

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

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

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

       BACKSPACE
              Delete the character to the left of the cursor,  or  cancel  the
              command if(3,n) 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(1,8) 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(3,n) they fit).

       ^U (Unix and OS/2) or ESC (MS-DOS)
              Delete  the  entire  command  line, or cancel the command if(3,n) the
              command line is empty.  If you have changed your line-kill char-
              acter in(1,8) Unix to something other than ^U, that character is used
              instead of ^U.


KEY BINDINGS
       You may define your own less(1,3) commands by using the program lesskey  (1)
       to  create  a  lesskey file.  This file(1,n) specifies a set(7,n,1 builtins) 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(7,n,1 builtins) environment
       variables.  If the environment variable LESSKEY is set(7,n,1 builtins), less(1,3) uses  that
       as  the  name of the lesskey file.  Otherwise, less(1,3) looks in(1,8) a standard
       place for the lesskey file: On Unix systems, less(1,3) looks for  a  lesskey
       file(1,n)  called  "$HOME/.less".  On MS-DOS and Windows systems, less(1,3) looks
       for a lesskey file(1,n) called "$HOME/_less", and if(3,n) it is not found  there,
       then looks for a lesskey file(1,n) called "_less" in(1,8) any directory specified
       in(1,8) the PATH environment variable.  On OS/2 systems, less(1,3)  looks  for  a
       lesskey  file(1,n)  called  "$HOME/less.ini",  and  if(3,n) it is not found, then
       looks for a lesskey file(1,n) called "less.ini" in(1,8) any  directory  specified
       in(1,8) the INIT environment variable, and if(3,n) it not found there, then looks
       for a lesskey file(1,n) called "less.ini" in(1,8) any directory specified in(1,8)  the
       PATH  environment  variable.   See  the  lesskey  manual  page for more
       details.

       A system-wide lesskey file(1,n) may also be set(7,n,1 builtins) up to provide key  bindings.
       If a key is defined in(1,8) both a local lesskey file(1,n) and in(1,8) the system-wide
       file(1,n), key bindings in(1,8) the local file(1,n) take precedence over those in(1,8)  the
       system-wide  file.   If the environment variable LESSKEY_SYSTEM is set(7,n,1 builtins),
       less(1,3) uses that as the name of the system-wide lesskey file.  Otherwise,
       less(1,3)  looks  in(1,8)  a  standard place for the system-wide lesskey file: On
       Unix systems, the system-wide lesskey file(1,n)  is  /usr/local/etc/sysless.
       (However,  if(3,n)  less(1,3)  was  built with a different sysconf directory than
       /usr/local/etc, that directory is where the sysless file(1,n) is found.)  On
       MS-DOS  and  Windows  systems, the system-wide lesskey file(1,n) is c:\_sys-
       less.  On OS/2 systems, the system-wide lesskey file(1,n) is c:\sysless.ini.


INPUT PREPROCESSOR
       You  may  define an "input preprocessor" for less.  Before less(1,3) opens a
       file(1,n), it first gives your input preprocessor a chance to modify the way
       the  contents of the file(1,n) are displayed.  An input preprocessor is sim-
       ply an executable program (or shell script), which writes the  contents
       of the file(1,n) to a different file(1,n), called the replacement file.  The con-
       tents of the replacement file(1,n) are then displayed in(1,8) place of  the  con-
       tents  of the original file.  However, it will appear to the user as if(3,n)
       the original file(1,n) is opened; that is, less(1,3) 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(1,n),  and when finished, print the name of the replacement file(1,n) to its
       standard output.  If the input preprocessor does not output a  replace-
       ment  filename, less(1,3) uses the original file(1,n), as normal.  The input pre-
       processor is not called when viewing standard  input.   To  set(7,n,1 builtins)  up  an
       input  preprocessor, set(7,n,1 builtins) the LESSOPEN environment variable to a command
       line which will invoke your  input  preprocessor.   This  command  line
       should  include  one  occurrence  of  the  string(3,n)  "%s",  which will be
       replaced by  the  filename  when  the  input  preprocessor  command  is
       invoked.

       When less(1,3) closes a file(1,n) opened in(1,8) such a way, it will call another pro-
       gram, called the input postprocessor, which  may  perform  any  desired
       clean-up  action  (such  as  deleting  the  replacement file(1,n) created by
       LESSOPEN).  This program receives two command line arguments, the orig-
       inal  filename  as entered by the user, and the name of the replacement
       file.  To set(7,n,1 builtins) up an input postprocessor, set(7,n,1 builtins) the LESSCLOSE  environment
       variable  to a command line which will invoke your input postprocessor.
       It may include two  occurrences  of  the  string(3,n)  "%s";  the  first  is
       replaced  with  the  original  name of the file(1,n) and the second with the
       name of the replacement file(1,n), which was output by LESSOPEN.

       For example, on many Unix systems, these two scripts will allow you  to
       keep files in(1,8) compressed format, but still let less(1,3) view them directly:

       lessopen.sh:
            #! /bin/sh
            case "$1" in(1,8)
            *.Z) uncompress -c $1  >/tmp/less.$$  2>/dev/null
                 if(3,n) [ -s /tmp/less.$$ ]; then
                      echo(1,3x,1 builtins) /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(7,n,1 builtins)
       LESSOPEN="lessopen.sh %s",  and  LESSCLOSE="lessclose.sh %s %s".   More
       complex LESSOPEN and LESSCLOSE scripts may be written to  accept(2,8)  other
       types of compressed files, and so on.

       It  is  also  possible to set(7,n,1 builtins) up an input preprocessor to pipe(2,8) the file(1,n)
       data directly to less(1,3), rather than putting the data into a  replacement
       file.  This avoids the need to decompress the entire file(1,n) before start-
       ing to view it.  An input preprocessor that works this way is called an
       input  pipe.   An input pipe(2,8), instead of writing the name of a replace-
       ment file(1,n) on its standard output, writes the  entire  contents  of  the
       replacement  file(1,n)  on  its standard output.  If the input pipe(2,8) does not
       write(1,2) any characters on its standard output, then there is no  replace-
       ment  file(1,n) and less(1,3) uses the original file(1,n), as normal.  To use an input
       pipe(2,8), make the first character in(1,8) the LESSOPEN environment  variable  a
       vertical  bar  (|)  to  signify that the input preprocessor is an input
       pipe.

       For example, on many Unix systems, this script will work like the  pre-
       vious example scripts:

       lesspipe.sh:
            #! /bin/sh
            case "$1" in(1,8)
            *.Z) uncompress -c $1  2>/dev/null
                 ;;
            esac

       To  use  this  script,  put  it  where  it  can  be  executed  and  set(7,n,1 builtins)
       LESSOPEN="|lesspipe.sh %s".  When an input pipe(2,8) is  used,  a  LESSCLOSE
       postprocessor  can be used, but it is usually not necessary since there
       is no replacement file(1,n) to clean up.  In this case, the replacement file(1,n)
       name passed to the LESSCLOSE postprocessor is "-".


NATIONAL CHARACTER SETS
       There are three types of characters in(1,8) 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(1,8) ordinary text files (such as backspace and tab).

       binary characters
              should not be displayed directly and  are  not  expected  to  be
              found in(1,8) text files.

       A "character set(7,n,1 builtins)" is simply a description of which characters are to be
       considered normal, control, and binary.   The  LESSCHARSET  environment
       variable  may  be  used to select(2,7,2 select_tut) a character set.  Possible values for
       LESSCHARSET are:

       ascii(1,7)  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(7,n,1 builtins) appropriate for MS-DOS.

       ebcdic Selects an EBCDIC character set.

       IBM-1047
              Selects an EBCDIC character set(7,n,1 builtins) 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(1,8) your
              environment.

       koi8-r Selects a Russian character set.

       next   Selects a character set(7,n,1 builtins) appropriate for NeXT computers.

       utf-8  Selects the UTF-8 encoding(3,n) of the ISO 10646 character set.

       In  special  cases, it may be desired to tailor less(1,3) to use a character
       set(7,n,1 builtins) 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(7,n,1 builtins) to a string(3,n) where each character in(1,8) the string(3,n)  repre-
       sents  one  character  in(1,8) the character set.  The character "." is used
       for a normal character, "c" for control, and "b" for binary.  A decimal
       number  may  be used for repetition.  For example, "bccc4b." would mean
       character 0 is binary, 1, 2 and 3 are  control,  4,  5,  6  and  7  are
       binary, and 8 is normal.  All characters after the last are taken to be
       the same as the last, so characters 9  through  255  would  be  normal.
       (This  is an example, and does not necessarily represent any real char-
       acter set.)

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

            ascii(1,7)     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(7,n,1 builtins), but the string(3,n) "UTF-8"
       is found in(1,8) the LC_ALL, LC_TYPE or LANG environment variables, then the
       default character set(7,n,1 builtins) is utf-8.

       If  that  string(3,n)  is  not found, but your system supports the setlocale
       interface, less(1,3) will use setlocale  to  determine  the  character  set.
       setlocale  is  controlled  by  setting the LANG or LC_CTYPE environment
       variables.

       Finally, if(3,n) the setlocale interface is also not available, the  default
       character set(7,n,1 builtins) is latin1.

       Control  and  binary  characters  are  displayed  in(1,8)  standout (reverse
       video).  Each such character is displayed in(1,8) caret notation if(3,n) possible
       (e.g.  ^A for control-A).  Caret notation is used only if(3,n) inverting the
       0100 bit results in(1,8) a normal printable character.  Otherwise, the char-
       acter  is displayed as a hex number in(1,8) angle brackets.  This format can
       be changed by setting the LESSBINFMT environment variable.   LESSBINFMT
       may begin with a "*" and one character to select(2,7,2 select_tut) 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(3,n)  which
       may  include one printf-style escape sequence (a % followed by x, X, o,
       d, etc.).  For example, if(3,n) LESSBINFMT is  "*u[%x]",  binary  characters
       are  displayed  in(1,8)  underlined hexadecimal surrounded by brackets.  The
       default if(3,n) no LESSBINFMT is specified is "*s<%X>".


PROMPTS
       The -P option allows you to tailor the prompt to your preference.   The
       string(3,n)  given  to  the  -P option replaces the specified prompt string.
       Certain characters in(1,8) the string(3,n) are interpreted specially.  The prompt
       mechanism  is  rather complicated to provide flexibility, but the ordi-
       nary user need not understand the details of constructing  personalized
       prompt strings.

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

       %bX    Replaced by the byte offset into the current input file.  The  b
              is followed by a single character (shown as X above) which spec-
              ifies the line whose byte offset is to be used.  If the  charac-
              ter  is a "t", the byte offset of the top line in(1,8) the display is
              used, an "m" means use the middle line, a "b" means use the bot-
              tom  line,  a "B" means use the line just after the bottom line,
              and a "j" means use the "target" line, as specified  by  the  -j
              option.

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

       %c     Replaced by the column number of the text appearing in(1,8) the first
              column of the screen.

       %dX    Replaced by the page number of a line in(1,8) 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(1,8) the input file(1,n), or equiva-
              lently, the page number of the last line in(1,8) the input file.

       %E     Replaced by the name of the editor (from the VISUAL  environment
              variable,  or  the  EDITOR environment variable if(3,n) VISUAL is not
              defined).  See the discussion of the LESSEDIT feature below.

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

       %i     Replaced by the index of the current file(1,n) in(1,8) the list  of  input
              files.

       %lX    Replaced  by  the  line number of a line in(1,8) 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(1,8) the input  file.

       %m     Replaced by the total number of input files.

       %pX    Replaced  by  the  percent into the current input file(1,n), 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(1,n), 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(3,n), but may appear anywhere.

       %x     Replaced by the name of the next input file(1,n) in(1,8) the list.

       If any item is unknown (for example, the file(1,n) size if(3,n) input is a pipe(2,8)),
       a question mark is printed instead.

       The  format  of  the  prompt string(3,n) can be changed depending on certain
       conditions.  A question mark followed by a single character  acts  like
       an  "IF":  depending  on the following character, a condition is evalu-
       ated.  If the condition is true, any characters following the  question
       mark  and  condition  character,  up  to  a period, are included in(1,8) 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(1,8)  the string(3,n) if(3,n) and only if(3,n) the IF condition is false.
       Condition characters (which follow a question mark) may be:

       ?a     True if(3,n) any characters have been included in(1,8) the prompt so  far.

       ?bX    True if(3,n) the byte offset of the specified line is known.

       ?B     True if(3,n) the size of current input file(1,n) is known.

       ?c     True if(3,n) the text is horizontally shifted (%c is not zero).

       ?dX    True if(3,n) the page number of the specified line is known.

       ?e     True if(3,n) at end-of-file.

       ?f     True  if(3,n)  there is an input filename (that is, if(3,n) input is not a
              pipe(2,8)).

       ?lX    True if(3,n) the line number of the specified line is known.

       ?L     True if(3,n) the line number of the last line in(1,8) the file(1,n) is known.

       ?m     True if(3,n) there is more than one input file.

       ?n     True if(3,n) this is the first prompt in(1,8) a new input file.

       ?pX    True if(3,n) the percent into the current input file(1,n), based  on  byte
              offsets, of the specified line is known.

       ?PX    True  if(3,n)  the percent into the current input file(1,n), based on line
              numbers, of the specified line is known.

       ?s     Same as "?B".

       ?x     True if(3,n) there is a next input file(1,n)  (that  is,  if(3,n)  the  current
              input file(1,n) 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(1,8) the prompt literally
       by preceding it with a backslash.

       Some examples:

       ?f%f:Standard input.

       This prompt prints the filename, if(3,n) known; otherwise the string(3,n)  "Stan-
       dard input".

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

       This  prompt  would print the filename, if(3,n) known.  The filename is fol-
       lowed by the line number, if(3,n) known, otherwise  the  percent  if(3,n)  known,
       otherwise  the  byte  offset  if(3,n)  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(1,n) %i of %m) ..?e(END) ?x- Next\: %x..%t

       This  prints  the  filename if(3,n) this is the first prompt in(1,8) a file(1,n), fol-
       lowed by the "file(1,n) N of N" message if(3,n) there  is  more  than  one  input
       file.   Then,  if(3,n)  we are at end-of-file, the string(3,n) "(END)" is printed
       followed by the name of the next file(1,n), if(3,n) there is one.   Finally,  any
       trailing spaces are truncated.  This is the default prompt.  For refer-
       ence, here are the defaults for  the  other  two  prompts  (-m  and  -M
       respectively).   Each  is  broken  into  two lines here for readability
       only.

       ?n?f%f .?m(file(1,n) %i of %m) ..?e(END) ?x- Next\: %x.:
            ?pB%pB\%:byte %bB?s/%s...%t

       ?f%f .?n?m(file(1,n) %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(1,n) %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(3,n)  an
       environment  variable LESSEDIT is defined, it is used as the command to
       be executed when the v command is  invoked.   The  LESSEDIT  string(3,n)  is
       expanded  in(1,8) 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(1,n) name.  If your editor does not accept(2,8) the
       "+linenumber" syntax, or has other differences  in(1,8)  invocation  syntax,
       the LESSEDIT variable can be changed to modify this default.


SECURITY
       When  the  environment  variable LESSSECURE is set(7,n,1 builtins) to 1, less(1,3) runs in(1,8) a
       "secure" mode.  This means these features are disabled:

              !      the shell command

              |      the pipe(2,8) 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(1,8) filenames, such as *

                     filename completion (TAB, ^L)

       Less can also be compiled to be permanently in(1,8) "secure" mode.


ENVIRONMENT VARIABLES
       Environment variables may be specified either in(1,8) the system environment
       as  usual,  or  in(1,8)  a  lesskey  (1) file.  If environment variables are
       defined in(1,8) more than one place, variables defined in(1,8)  a  local  lesskey
       file(1,n)  take precedence over variables defined in(1,8) the system environment,
       which take precedence over variables defined in(1,8) 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(3,n)
              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(1,n)
              on Unix and OS/2 systems).

       HOMEDRIVE, HOMEPATH
              Concatenation of the HOMEDRIVE and  HOMEPATH  environment  vari-
              ables is the name of the user's home directory if(3,n) the HOME vari-
              able is not set(7,n,1 builtins) (only in(1,8) the Windows version(1,3,5)).

       INIT   Name of the user's init directory (used to find a  lesskey  file(1,n)
              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(1,3) automatically.

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

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

       LESSCHARDEF
              Defines a character set.

       LESSCHARSET
              Selects a predefined character set.

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

       LESSECHO
              Name of the lessecho program (default "lessecho").  The lessecho
              program  is needed to expand metacharacters, such as * and ?, in(1,8)
              filenames on Unix systems.

       LESSEDIT
              Editor prototype string(3,n) (used for the v command).   See  discus-
              sion under PROMPTS.

       LESSGLOBALTAGS
              Name  of  the command used by the -t option to find global tags.
              Normally should be set(7,n,1 builtins) to "global" if(3,n) your system has the global
              (1) command.  If not set(7,n,1 builtins), global tags are not used.

       LESSKEY
              Name of the default lesskey(1) file.

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

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

       LESSMETAESCAPE
              Prefix which less(1,3) will add before each metacharacter in(1,8)  a  com-
              mand  sent  to the shell.  If LESSMETAESCAPE is an empty string(3,n),
              commands containing metacharacters will not  be  passed  to  the
              shell.

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

       LESSSECURE
              Runs less(1,3) in(1,8) "secure" mode.  See discussion under SECURITY.

       LESSSEPARATOR
              String  to  be  appended to a directory name in(1,8) filename comple-
              tion.

       LINES  Sets the number of lines on the screen.  Takes  precedence  over
              the number of lines specified by the TERM variable.  (But if(3,n) 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(1,n)  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(1,3) is being run.

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


SEE ALSO
       lesskey(1)


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

       If the :e command is used to name more than one file(1,n), and  one  of  the
       named(5,8)  files  has  been viewed previously, the new files may be entered
       into the list in(1,8) an unexpected order.

       On certain older terminals (the so-called  "magic(4,5)  cookie"  terminals),
       search  highlighting  will  cause an erroneous display.  On such termi-
       nals, search highlighting is disabled  by  default  to  avoid  possible
       problems.

       In certain cases, when search highlighting is enabled and a search pat-
       tern begins with a ^, more text than the matching string(3,n) may  be  high-
       lighted.  (This problem does not occur when less(1,3) is compiled to use the
       POSIX regular expression package.)

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

       On  some  systems, setlocale claims that ASCII characters 0 thru 31 are
       control characters rather than binary characters.  This causes less(1,3)  to
       treat  some  binary files as ordinary, non-binary files.  To workaround
       this problem, set(7,n,1 builtins) the environment variable LESSCHARSET to  "ascii(1,7)"  (or
       whatever character set(7,n,1 builtins) is appropriate).

       See  http://www.greenwoodsoftware.com/less(1,3) for the latest list of known
       bugs in(1,8) this version(1,3,5) of less.


COPYRIGHT
       Copyright (C) 2002  Mark Nudelman

       less(1,3) is part of the GNU project and is free software.  You  can  redis-
       tribute  it and/or modify it under the terms of either (1) the GNU Gen-
       eral Public License as published by the Free  Software  Foundation;  or
       (2) the Less License.  See the file(1,n) README in(1,8) the less(1,3) distribution for
       more details regarding redistribution.  You should have received a copy
       of  the  GNU General Public License along with the source for less(1,3); see
       the file(1,n) COPYING.  If not, write(1,2) 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(1,n) LICENSE.

       less(1,3) is distributed in(1,8) the hope that it will be useful, but WITHOUT ANY
       WARRANTY;  without even the implied warranty of MERCHANTABILITY or FIT-
       NESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License  for
       more details.


AUTHOR
       Mark Nudelman <markn@greenwoodsoftware.com>
       Send  bug  reports  or  comments  to  the  above  address  or  to  bug-
       less(1,3)@gnu.org.
       For more information, see the less(1,3)  homepage  at  http://www.greenwood-
       software.com/less.



                           Version 382: 03 Feb 2004                    LESS(1)

References for this manual (incoming links)