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LESS(1)                                                                                              LESS(1)



NAME
       less - opposite of more

SYNOPSIS
       less -?
       less --help
       less -V
       less --version
       less [-[+]aBcCdeEfFgGiIJKLmMnNqQrRsSuUVwWX~]
            [-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 for-ward forward
       ward 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 pre-fixed prefixed
       fixed 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.

       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 com-mand command
              mand 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 brack-ets, brackets,
              ets, 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 brack-
              ets, 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 previ-ously previously
              ously 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 second 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, regard-less regardless
                     less 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 compar-ison. comparison.
                     ison.

       ?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  pre-vious previous
              vious  search  was  modified by ^E, the search continues in the next (or previous) file if not
              satisfied in the current file.  If the previous search was modified by ^R, the search is  done
              without  using regular expressions.  There is no effect if the previous search was modified by
              ^F or ^K.

       N      Repeat previous search, but in the reverse direction.

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

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

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

       :e [filename]
              Examine  a  new  file.  If the filename is missing, the "current" file (see the :n and :p com-mands commands
              mands 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 per-cent percent
              cent 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 sys-tems, systems,
              tems, 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 pre-vious previous
              vious 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 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 -  com-mand. command.
              mand.

       -+     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 "oppo-site" "opposite"
              site" 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 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  envi-ronment environment
              ronment 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 abbrevi-ation abbreviation
       ation  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  equiva-lent equivalent
       lent 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
              Causes  searches to start after the last line displayed on the screen, thus skipping all lines
              displayed on the screen.  By default, searches start at the second  line  on  the  screen  (or
              after the last found line; see the -j option).

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

       -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 direc-tories directories
              tories 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.  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 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 num-ber number
              ber 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  confirma-tion. confirmation.
              tion.

              If no log file has been specified, the -o and -O options can be used from within less to spec-ify specify
              ify 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 mes-sage message
              sage 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, var-ious various
              ious 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 por-tion portion
              tion  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 cur-rent current
              rent directory called "tags", which was previously built by ctags (1) or  an  equivalent  com-mand. command.
              mand.  If the environment variable LESSGLOBALTAGS is set, it is taken to be the name of a com-mand command
              mand 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  hard-ware hardware
              ware  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  con-tinue continue
              tinue  with  the same spacing as the last two.  For example, -x9,17 will set tabs at positions
              9, 17, 25, 33, etc.  The default for n is 8.

       -X or --no-init
              Disables sending the termcap initialization and  deinitialization  strings  to  the  terminal.
              This  is  sometimes  desirable if the deinitialization string does something unnecessary, like
              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 compat-ibility compatibility
              ibility  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 LEFTAR-ROW LEFTARROW
              ROW commands.  If the number specified is zero, it sets the default number of positions to one
              half 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 speci-fied, specified,
              fied, 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  dis-play display
              play 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  par-ticular particular
       ticular  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 file-name, filename,
              name, 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 file-name, filename,
              name, 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.


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 systemwide
       wide  lesskey  file:  On Unix systems, the system-wide lesskey file is /usr/local/etc/sysless.  (How-ever, (However,
       ever, 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 preproces-sor preprocessor
       sor 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  origi-nal original
       nal 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 postpro-cessor, postprocessor,
       cessor,  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  for-mat, format,
       mat, but still let less view them directly:

       lessopen.sh:
            #! /bin/sh
            case "$1" in
            *.Z) uncompress -if uncompressif
                 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 "-".


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  sup-ports supports
              ports  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_TYPE or LANG environment variables, then the default character set
       is utf-8.

       If that string is not found, but your system supports the setlocale interface, less will  use  setlo-cale setlocale
       cale  to  determine the character set.  setlocale is controlled by setting the LANG or LC_CTYPE envi-ronment environment
       ronment 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 dis-played displayed
       played in caret notation if possible (e.g. ^A for control-A).  Caret notation is used only if invert-ing inverting
       ing 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 vari-able. variable.
       able.  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 LESS-BINFMT LESSBINFMT
       BINFMT is "*u[%x]", binary characters are displayed in underlined hexadecimal surrounded by brackets.
       The  default if no LESSBINFMT is specified is "*s<%X>".  The default if no LESSBINFMT is specified is
       "*s<%02X>".  Warning: the result of expanding the character via LESSBINFMT must be less than 31 char-acters. characters.
       acters.

       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 LESS-BINFMT LESSBINFMT
       BINFMT 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  char-acter character
              acter  (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 bot-tom bottom
              tom 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  envi-ronment environment
              ronment variable if VISUAL is not defined).  See the discussion of the LESSEDIT feature below.

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

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

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

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

       %m     Replaced by the total number of input files.

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

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

       %s     Same as %B.

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

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

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

       The format of the prompt string can be changed depending on certain conditions.  A question mark fol-lowed followed
       lowed 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 char-acter, character,
       acter, 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 invoca-tion invocation
       tion 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 speci-fied specified
              fied 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 COL-UMNS COLUMNS
              UMNS 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  invoca-tions invocations
              tions  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 LESS-METAESCAPE LESSMETAESCAPE
              METAESCAPE 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 COL-UMNS COLUMNS
              UMNS 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) 1984-2007  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>
       See http://www.greenwoodsoftware.com/less/bugs.html for the latest list of known bugs in less.
       Send bug reports or comments to the above address or to
       bug-less@gnu.org.
       For more information, see the less homepage at
       http://www.greenwoodsoftware.com/less.



                                          Version 418: 02 Jan 2008                                   LESS(1)

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