


LESS(1)                                                   LESS(1)


NNAAMMEE
       less - opposite of more

SSYYNNOOPPSSIISS
       lleessss --??
       lleessss ----hheellpp
       lleessss --VV
       lleessss ----vveerrssiioonn
       lleessss [[--[[++]]aaBBccCCddeeEEffggGGiiIImmMMnnNNqqQQrrssSSuuUUVVwwXX]]
            [[--bb _b_u_f_s]] [[--hh _l_i_n_e_s]] [[--jj _l_i_n_e]] [[--kk _k_e_y_f_i_l_e]]
            [[--{{ooOO}} _l_o_g_f_i_l_e]] [[--pp _p_a_t_t_e_r_n]] [[--PP _p_r_o_m_p_t]] [[--tt _t_a_g]]
            [[--TT _t_a_g_s_f_i_l_e]] [[--xx _t_a_b]] [[--yy _l_i_n_e_s]] [[--[[zz]] _l_i_n_e_s]]
            [[++[[++]]_c_m_d]] [[----]] [[_f_i_l_e_n_a_m_e]]......


DDEESSCCRRIIPPTTIIOONN
       _L_e_s_s  is  a  program similar to _m_o_r_e (1), but which allows
       backward movement in the file as well as forward movement.
       Also,  _l_e_s_s  does  not  have to read the entire input file
       before starting, so with large input files  it  starts  up
       faster  than  text editors like _v_i (1).  _L_e_s_s 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 _m_o_r_e and _v_i_.  Commands  may  be
       preceded by a decimal number, called N in the descriptions
       below.  The number is used by some commands, as indicated.


CCOOMMMMAANNDDSS
       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.  Warn-
              ing:  some  systems use ^V as a special literaliza-
              tion 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.




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LESS(1)                                                   LESS(1)


       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  8.
              This  behaves  best  if  you also set the -S option
              (chop lines).  Note that if you  wish  to  enter  a
              number  N,  you  must  use  ESC-),  not RIGHTARROW,
              because the arrow is taken to  be  a  line  editing
              command (see the LINE EDITING section).

       ESC-( or LEFTARROW
              Scroll horizontally left N characters, default 8.

       r or ^R or ^L
              Repaint the screen.

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

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




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LESS(1)                                                   LESS(1)


       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.

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

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

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

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

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

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

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

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

       m      Followed by any lowercase letter, marks the current



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LESS(1)                                                   LESS(1)


              position with that letter.

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

       ^X^X   Same as single quote.

       /pattern
              Search  forward  in the file for the N-th line con-
              taining the pattern.  N defaults to 1.  The pattern
              is  a regular expression, as recognized by _e_d_.  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 pat-
                     tern.

              ^E or *
                     Search multiple  files.   That  is,  if  the
                     search  reaches  the END of the current file
                     without finding a match, the search  contin-
                     ues  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 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 metachar-
                     acters; that is, do a simple textual compar-
                     ison.

       ?pattern
              Search backward in the file for the N-th line  con-
              taining the pattern.  The search starts at the line



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LESS(1)                                                   LESS(1)


              immediately before the top line displayed.

              Certain characters are special as in the / command:

              ^N or !
                     Search for lines which do NOT match the pat-
                     tern.

              ^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 com-
                     mand line list.

              ^F or @
                     Begin the search at the  last  line  of  the
                     last  file in the command line list, regard-
                     less 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 modi-
              fied by ^N, the search is made for  the  N-th  line
              NOT containing the pattern.  If the previous search
              was modified by ^E, the  search  continues  in  the
              next  (or  previous)  file  if not satisfied in the
              current file.  If the previous search was  modified
              by  ^R,  the  search  is done without using regular
              expressions.  There is no effect  if  the  previous
              search was modified by ^F or ^K.

       N      Repeat  previous  search, but in the reverse direc-
              tion.

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

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

       ESC-u  Undo search highlighting.  Turn off highlighting of



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LESS(1)                                                   LESS(1)


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

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

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

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

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

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

       = 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.




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LESS(1)                                                   LESS(1)


       -      Followed  by one of the command line option letters
              (see below), this will change the setting  of  that
              option  and print a message describing the new set-
              ting.  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 noth-
              ing is changed.

       -+     Followed  by one of the command line option letters
              (see below), 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.

       --     Followed by one of the command line option  letters
              (see  below),  this  will  reset  the option to the
              "opposite" of its default setting and print a  mes-
              sage  describing  the new setting.  (The "--_X" com-
              mand does the same thing as  "-_X"  on  the  command
              line.)   This  does not work for numeric or string-
              valued options.

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

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

       V      Prints the version number of _l_e_s_s being run.

       q or Q or :q or :Q or ZZ
              Exits _l_e_s_s_.

       The following four commands  may  or  may  not  be  valid,
       depending on your particular installation.


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

       ! shell-command
              Invokes a shell to run the shell-command given.   A
              percent  sign (%) in the command is replaced by the



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LESS(1)                                                   LESS(1)


              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  environ-
              ment  variable  SHELL, or defaults to "sh".  On MS-
              DOS and OS/2 systems, the shell is the normal  com-
              mand 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.


OOPPTTIIOONNSS
       Command line options are described  below.   Most  options
       may be changed while _l_e_s_s is running, via the "-" command.

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

       setenv LESS "-options"

       or if you use _s_h_:

       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 environ-
       ment variable.  If an option appears in the LESS variable,
       it  can  be  reset  to  its default 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"




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LESS(1)                                                   LESS(1)


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

       --help Same as -?.

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

       -b_n    Specifies  the  number of buffers _l_e_s_s will use for
              each file.  Buffers  are  1K,  and  by  default  10
              buffers  are used for each file (except if the file
              is a pipe; see the -B option).  The number _n speci-
              fies a different number of buffers to use.

       -B     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  the  number  of
              buffers specified by the -b option are used.  Warn-
              ing: use of -B can  result  in  erroneous  display,
              since  only  the  most  recently viewed part of the
              file is kept in memory; any earlier data is lost.

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

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

       -Dxx_c_o_l_o_r
              [MS-DOS only] Sets the color of the text displayed.
              xx is a single character which selects the  type  of
              text  whose  color is being set: n=normal, s=stand-
              out, d=bold, u=underlined,  k=blink.   _c_o_l_o_r  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



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LESS(1)                                                   LESS(1)


              number _N is the same as _N_._0.

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

       -E     Causes _l_e_s_s to automatically exit the first time it
              reaches end-of-file.

       -f     Forces non-regular files to be opened.  (A non-reg-
              ular file is a directory or a device special file.)
              Also  suppresses  the warning message when a binary
              file is opened.  By default, _l_e_s_s  will  refuse  to
              open non-regular files.

       -g     Normally,  _l_e_s_s  will  highlight  ALL strings which
              match the  last  search  command.   The  -g  option
              changes this behavior to highlight only the partic-
              ular string which was found by the last search com-
              mand.   This  can cause _l_e_s_s to run somewhat faster
              than the default.

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

       -h_n    Specifies a maximum number of lines to scroll back-
              ward.  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     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     Like -i, but searches ignore case even if the  pat-
              tern contains uppercase letters.

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



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LESS(1)                                                   LESS(1)


              screen, so searches begin at the fifth line on  the
              screen.

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

       -m     Causes _l_e_s_s to prompt verbosely (like  _m_o_r_e),  with
              the  percent  into  the  file.   By  default,  _l_e_s_s
              prompts with a colon.

       -M     Causes _l_e_s_s to  prompt  even  more  verbosely  than
              _m_o_r_e_.

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

       -N     Causes  a line number to be displayed at the begin-
              ning of each line in the display.

       -o_f_i_l_e_n_a_m_e
              Causes _l_e_s_s 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, _l_e_s_s will ask for confirmation
              before overwriting it.

       -O_f_i_l_e_n_a_m_e
              The -O option is like -o, but it will overwrite  an
              existing file without asking for confirmation.

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

       -p_p_a_t_t_e_r_n
              The  -p option on the command line is equivalent to
              specifying +/_p_a_t_t_e_r_n; that is,  it  tells  _l_e_s_s  to
              start  at  the  first  occurrence of _p_a_t_t_e_r_n in the
              file.




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LESS(1)                                                   LESS(1)


       -P_p_r_o_m_p_t
              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 _l_e_s_s 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.   All
              prompt strings consist of a sequence of letters and
              special  escape  sequences.   See  the  section  on
              PROMPTS for more details.

       -q     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     Causes totally "quiet" operation: the terminal bell
              is never rung.

       -r     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,  _l_e_s_s  cannot  keep  track of the
              actual appearance of the screen (since this depends
              on  how the screen responds to each type of control
              character).  Thus,  various  display  problems  may
              result, such as long lines being split in the wrong
              place.

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

       -S     Causes lines longer than the  screen  width  to  be
              chopped rather than folded.  That is, the remainder
              of a long line is simply discarded.  The default is
              to  fold long lines; that is, display the remainder
              on the next line.

       -t_t_a_g  The -t option, followed immediately by a TAG,  will
              edit  the  file  containing  that tag.  For this to
              work, there must be a file  called  "tags"  in  the
              current  directory,  which  was previously built by
              the _c_t_a_g_s (1) command.  This  option  may  also  be



                     Version 337: 09 Apr 1999                  12





LESS(1)                                                   LESS(1)


              specified from within _l_e_s_s (using the - command) as
              a way of examining a new file.  The command ":t" is
              equivalent to specifying -t from within _l_e_s_s_.

       -T_t_a_g_s_f_i_l_e
              Specifies a tags file to be used instead of "tags".

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

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

       -V     Displays the version number of _l_e_s_s_.

       --version
              Same as -V.

       -w     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.  The high-
              light is removed at the next command  which  causes
              movement.

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

       -x_n    Sets  tab stops every _n positions.  The default for
              _n is 8.

       -X     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.



                     Version 337: 09 Apr 1999                  13





LESS(1)                                                   LESS(1)


       -y_n    Specifies a maximum number of lines to scroll  for-
              ward.   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  Changes  the  default  scrolling  window  size to _n
              lines.  The default is one screenful.  The z and  w
              commands  can  also  be  used  to change the window
              size.  The "z" may  be  omitted  for  compatibility
              with  _m_o_r_e_.   If the number _n is negative, it indi-
              cates _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 automati-
              cally changes to 36 lines.

       -"     Changes the filename quoting character.   This  may
              be necessary if you are trying to name a file which
              contains both spaces and  quote  characters.   Fol-
              lowed 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  char-
              acter.  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).

       --     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 remain-
              der of that option is taken to be an  initial  com-
              mand  to _l_e_s_s_.  For example, +G tells _l_e_s_s 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 dis-
              play 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.





                     Version 337: 09 Apr 1999                  14





LESS(1)                                                   LESS(1)


LLIINNEE EEDDIITTIINNGG
       When entering command line at the  bottom  of  the  screen
       (for  example,  a filename for the :e command, or the pat-
       tern for a search command), certain keys can  be  used  to
       manipulate the command line.  Most commands have an alter-
       nate form in [ brackets ] which can be used if a key  does
       not  exist on a particular keyboard.  (The bracketed forms
       do not work in the MS-DOS version.)  Any of these  special
       keys  may  be  entered  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



                     Version 337: 09 Apr 1999                  15





LESS(1)                                                   LESS(1)


              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 direc-
              tory, a "/" is appended to the filename.   (On  MS-
              DOS  systems,  a "\" is appended.)  The environment
              variable LESSSEPARATOR can be  used  to  specify  a
              different  character to append to a directory name.

       BACKTAB [ ESC-TAB ]
              Like, TAB, but cycles in the reverse direction thru
              the matching filenames.

       ^L     Complete  the  partial  filename to the left of the
              cursor.  If it matches more than one filename,  all
              matches  are entered into the command line (if they
              fit).

       ^U (Unix) or ESC (MS-DOS)
              Delete the entire command line, or cancel the  com-
              mand  if  the  command  line is empty.  If you have
              changed your line-kill character in Unix  to  some-
              thing other than ^U, that character is used instead
              of ^U.


KKEEYY BBIINNDDIINNGGSS
       You may define your own _l_e_s_s commands by using the program
       _l_e_s_s_k_e_y (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 _l_e_s_s_k_e_y to change the line-editing
       keys (see LINE EDITING), and to set environment variables.
       If the environment variable LESSKEY is set, _l_e_s_s uses that
       as the name of the lesskey file.  Otherwise, _l_e_s_s looks in
       a  standard  place  for the lesskey file: On Unix systems,
       _l_e_s_s looks for a lesskey file  called  "$HOME/.less".   On
       MS-DOS  systems,  _l_e_s_s  looks  for  a  lesskey file called
       "$HOME/_less", and if it is not found  there,  then  looks
       for  a lesskey file called "_less" in any directory speci-
       fied in the PATH environment variable.  On  OS/2  systems,
       _l_e_s_s 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 environ-
       ment 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 _l_e_s_s_k_e_y  manual
       page for more details.


IINNPPUUTT PPRREEPPRROOCCEESSSSOORR
       You  may  define an "input preprocessor" for _l_e_s_s_.  Before
       _l_e_s_s opens a file, it first gives your input  preprocessor
       a  chance  to  modify the way the contents of the file are
       displayed.  An input preprocessor is simply an  executable



                     Version 337: 09 Apr 1999                  16





LESS(1)                                                   LESS(1)


       program  (or  shell  script), which writes the contents of
       the file to a different file, called the replacement file.
       The contents of the replacement file are then displayed in
       place of the contents of the original file.   However,  it
       will appear to the user as if the original file is opened;
       that is, _l_e_s_s 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 file-
       name, _l_e_s_s 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 environ-
       ment  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 _l_e_s_s closes a file opened in such a way, it will call
       another program, called the input postprocessor, which may
       perform  any desired clean-up action (such as deleting the
       replacement  file  created  by  LESSOPEN).   This  program
       receives two command line arguments, the original filename
       as entered by the user, and the name  of  the  replacement
       file.  To set up an input postprocessor, set the LESSCLOSE
       environment variable to a command line which  will  invoke
       your  input postprocessor.  It may include two occurrences
       of the string "%s"; the first is replaced with the  origi-
       nal  name  of the file and the second with the name of the
       replacement file, which was output by LESSOPEN.

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

       lessopen.sh:
            #! /bin/sh
            case "$1" in
            *.Z) uncompress -c $1  >/tmp/less.$$  2>/dev/null
                 if [ -s /tmp/less.$$ ]; then
                      echo /tmp/less.$$
                 else
                      rm -f /tmp/less.$$
                 fi
                 ;;
            esac

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



                     Version 337: 09 Apr 1999                  17





LESS(1)                                                   LESS(1)


       To use these scripts, put them both where they can be exe-
       cuted     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 _l_e_s_s_, 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
       _l_e_s_s 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 pre-
       processor 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 "-".


NNAATTIIOONNAALL CCHHAARRAACCTTEERR SSEETTSS
       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.




                     Version 337: 09 Apr 1999                  18





LESS(1)                                                   LESS(1)


       A "character set" is simply a description of which charac-
       ters  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  The  default  character  set.  BS, TAB, NL, CR, and
              formfeed are control  characters,  all  chars  with
              values  between 32 and 126 are normal, and all oth-
              ers are binary.

       iso8859
              Selects the ISO 8859/1 character set.   latin-1  is
              the  same  as  ASCII, except characters between 161
              and 255 are treated as normal characters.

       latin1 Same as iso8859.

       dos    Selects a character set appropriate for MS-DOS.

       ebcdic Selects an EBCDIC character set.

       koi8-r Selects a Russian character set.

       next   Selects a character set appropriate for  NeXT  com-
              puters.

       In  special cases, it may be desired to tailor _l_e_s_s to use
       a character set other than the  ones  definable  by  LESS-
       CHARSET.   In  this  case,  the environment variable LESS-
       CHARDEF can be used to define a character set.  It  should
       be set to a string where each character in the string rep-
       resents 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  repeti-
       tion.   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 neces-
       sarily represent any real character set.)

       This table shows the value of LESSCHARDEF which is equiva-
       lent 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.
            iso8859   8bcccbcc18b95.33b.
            koi8-r    8bcccbcc18b95.b128.
            latin1    8bcccbcc18b95.33b.
            next      8bcccbcc18b95.bb125.bb

       If  neither  LESSCHARSET  nor LESSCHARDEF is set, but your



                     Version 337: 09 Apr 1999                  19





LESS(1)                                                   LESS(1)


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

       Control  and  binary  characters are displayed in standout
       (reverse video).  Each  such  character  is  displayed  in
       caret notation if possible (e.g. ^A for control-A).  Caret
       notation is used only if inverting the 0100 bit results in
       a normal printable character.  Otherwise, the character is
       displayed as a hex number in angle brackets.  This  format
       can be changed by setting the LESSBINFMT environment vari-
       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  is  "*u[%x]",  binary  characters are displayed in
       underlined  hexadecimal  surrounded  by   brackets.    The
       default if no LESSBINFMT is specified is "*s<%X>".


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

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

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

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

       %d_X    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



                     Version 337: 09 Apr 1999                  20





LESS(1)                                                   LESS(1)


              in the input file.

       %E     Replaced by the name of the editor (from the VISUAL
              environment  variable,  or  the  EDITOR environment
              variable if VISUAL is not defined).  See  the  dis-
              cussion 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.

       %l_X    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.

       %p_X    Replaced  by  the  percent  into  the current input
              file.  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  any-
              where.

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

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

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

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




                     Version 337: 09 Apr 1999                  21





LESS(1)                                                   LESS(1)


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

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

       ?d_X    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).

       ?l_X    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.

       ?p_X    True if the percent into the current input file  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 file-
       name 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.




                     Version 337: 09 Apr 1999                  22





LESS(1)                                                   LESS(1)


       ?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 refer-
       ence, here are the defaults for the other two prompts  (-m
       and  -M respectively).  Each is broken into two lines here
       for readability only.

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

       ?f%f .?n?m(file %i of %m) ..?ltline %lt?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) .?ltline %lt?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 com-
       mand is invoked.  The LESSEDIT string is expanded  in  the
       same  way  as  the  prompt strings.  The default value for
       LESSEDIT is:

            %E ?lm+%lm. %f

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


SSEECCUURRIITTYY
       When the environment variable LESSSECURE is set to 1, _l_e_s_s
       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




                     Version 337: 09 Apr 1999                  23





LESS(1)                                                   LESS(1)


              -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.


EENNVVIIRROONNMMEENNTT VVAARRIIAABBLLEESS
       Environment  variables may be specified either in the sys-
       tem environment as usual, or in a _l_e_s_s_k_e_y (1) file.

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

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

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

       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 _l_e_s_s automatically.

       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-post-
              processor.




                     Version 337: 09 Apr 1999                  24





LESS(1)                                                   LESS(1)


       LESSECHO
              Name of the lessecho program (default  "lessecho").
              The  lessecho program is needed to expand metachar-
              acters, such as * and ?, in filenames on Unix  sys-
              tems.

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

       LESSKEY
              Name of the default lesskey(1) file.

       LESSMETACHARS
              List of characters which are considered  "metachar-
              acters" by the shell.

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

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

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

       LESSSEPARATOR
              String to be appended to a directory name in  file-
              name completion.

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

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

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

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

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





                     Version 337: 09 Apr 1999                  25





LESS(1)                                                   LESS(1)


SSEEEE AALLSSOO
       lesskey(1)


WWAARRNNIINNGGSS
       The  =  command  and prompts (unless changed by -P) report
       the line number of the line at the top of the screen,  but
       the  byte  and  percent  of  the line at the bottom of the
       screen.

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

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

       In certain cases, when search highlighting is enabled  and
       a  search  pattern  begins  with  a  ^, more text than the
       matching string may be highlighted.   (This  problem  does
       not  occur  when less is compiled to use the POSIX regular
       expression package.)

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


CCOOPPYYRRIIGGHHTT
       Copyright   (c)  1984,1985,1989,1994,1995,1996,1999   Mark
       Nudelman
       Comments to: marknu@flash.net




















                     Version 337: 09 Apr 1999                  26


