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|
LESS(1) LESS(1)
NNAAMMEE
less - opposite of more
SSYYNNOOPPSSIISS
lleessss --??
lleessss ----hheellpp
lleessss --VV
lleessss ----vveerrssiioonn
lleessss [[--[[++]]aaBBccCCddeeEEffFFggGGiiIIJJLLmmMMnnNNqqQQrrRRssSSuuUUVVwwWWXX~~]]
[[--bb _s_p_a_c_e]] [[--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]]
[[--## _s_h_i_f_t]] [[++[[++]]_c_m_d]] [[----]] [[_f_i_l_e_n_a_m_e]]......
(See the OPTIONS section for alternate option syntax with
long option names.)
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
Version 381: 17 Jan 2003 1
LESS(1) LESS(1)
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 command
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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.
{ 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,
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respectively. For example, "ESC ^B < >" could be
used to go backward to the < which matches the > in
the bottom displayed line.
m Followed by any lowercase letter, marks the current
position with that letter.
' (Single quote.) Followed by any lowercase letter,
returns to the position which was previously marked
with that letter. Followed by another single
quote, returns to the position at which the last
"large" movement command was executed. Followed by
a ^ or $, jumps to the beginning or end of the file
respectively. Marks are preserved when a new file
is examined, so the ' command can be used to switch
between input files.
^X^X Same as single quote.
/pattern
Search forward in the file for the N-th line 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
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comparison.
?pattern
Search backward in the file for the N-th line con
taining 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 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 *.
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ESC-N Repeat previous search, but in the reverse direc
tion and crossing file boundaries.
ESC-u Undo search highlighting. Turn off highlighting of
strings matching the current search pattern. If
highlighting is already off because of a previous
ESC-u command, turn highlighting back on. Any
search command will also turn highlighting back on.
(Highlighting can also be disabled by toggling the
-G option; in that case search commands do not turn
highlighting back on.)
: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.
: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
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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 imme
diately 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 - command.
-+ Followed by one of the command line option letters
this will reset the option to its default setting
and print a message describing the new setting.
(The "-+_X" command does the same thing as "-+_X" on
the command line.) This does not work for string-
valued options.
--+ Like the -+ command, but takes a long option name
rather than a single option letter.
-! Followed by one of the command line option letters,
this will reset the option to the "opposite" of its
default setting and print a message describing the
new setting. This does not work for numeric or
string-valued options.
--! Like the -! command, but takes a long option name
rather than a single option letter.
_ (Underscore.) Followed by one of the command line
option letters, this will print a message describ
ing the current setting of that option. The
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setting of the option is not changed.
__ (Double underscore.) Like the _ (underscore) com
mand, 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 _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
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.
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OOPPTTIIOONNSS
Command line options are described below. Most options
may be changed while _l_e_s_s 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 abbrevi
ated as long as the abbreviation is unambiguous. For
example, --quit-at-eof may be abbreviated --quit, but not
--qui, since both --quit-at-eof and --quiet begin with
--qui. Some long option names are in uppercase, such as
--QUIT-AT-EOF, as distinct from --quit-at-eof. Such
option names need only have their first letter capital
ized; the remainder of the name may be in either case.
For example, --Quit-at-eof is equivalent to --QUIT-AT-EOF.
Options are also taken from the environment variable
"LESS". For example, to avoid typing "less -options ..."
each time _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 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 _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: "-\?".)
-a or --search-skip-screen
Causes searches to start after the last line dis
played on the screen, thus skipping all lines
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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).
-b_n or --buffers=_n
Specifies the amount of buffer space _l_e_s_s 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 is 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 erro
neous display, since only the most recently viewed
part of the file 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
The -C option is like -c, but the screen is cleared
before it is repainted.
-d or --dumb
The -d option suppresses the error message normally
displayed if the terminal is dumb; that is, lacks
some important capability, such as the ability to
clear the screen or scroll backward. The -d option
does not otherwise change the behavior of _l_e_s_s on a
dumb terminal.
-Dxx_c_o_l_o_r or --color=xx_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
number _N is the same as _N_._0.
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-e or --quit-at-eof
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 or --QUIT-AT-EOF
Causes _l_e_s_s to automatically exit the first time it
reaches end-of-file.
-f or --force
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.
-F or --quit-if-one-screen
Causes _l_e_s_s to automatically exit if the entire
file can be displayed on the first screen.
-g or --hilite-search
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 or --HILITE-SEARCH
The -G option suppresses all highlighting of
strings found by search commands.
-h_n or ---max-back-scroll=_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 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 pat
tern contains uppercase letters.
-j_n or --jump-target=_n
Specifies a line on the screen where the "target"
line is to be positioned. A target line is the
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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
screen, so searches begin at the fifth line on the
screen.
-J or --status-column
Displays a status column at the left edge of the
screen. The status column shows the lines that
matched the current search. The status column is
also used if the -w or -W option is in effect.
-k_f_i_l_e_n_a_m_e or --lesskey-file=_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 or LESSKEY_SYSTEM envi
ronment 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.
-L or --no-lessopen
Ignore the LESSOPEN environment variable (see the
INPUT PREPROCESSOR section below). This option can
be set from within _l_e_s_s, but it will apply only to
files opened subsequently, not to the file which is
currently open.
-m or --long-prompt
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 or --LONG-PROMPT
Causes _l_e_s_s to prompt even more verbosely than
_m_o_r_e_.
-n or --line-numbers
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).
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-N or --LINE-NUMBERS
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 or --log-file=_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 or --LOG-FILE=_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 or --pattern=_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.
-P_p_r_o_m_p_t or --prompt=_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. -Pw
changes the message printed while waiting for data
(in the F command). All prompt strings consist of
a sequence of letters and special escape sequences.
See the section on PROMPTS for more details.
-q or --quiet or --silent
Causes moderately "quiet" operation: the terminal
bell is not rung if an attempt is made to scroll
past the end of the file or before the beginning of
the file. If the terminal has a "visual bell", it
is used instead. The bell will be rung on certain
other errors, such as typing an invalid character.
The default is to ring the terminal bell in all
such cases.
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-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, _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.
-R or --RAW-CONTROL-CHARS
Like -r, but tries to keep track of the screen
appearance where possible. This works only if the
input consists of normal text and possibly some
ANSI "color" escape sequences, which are sequences
of the form:
ESC [ ... m
where the "..." is zero or more characters other
than "m". For the purpose of keeping track of
screen appearance, all control characters and all
ANSI color escape sequences are assumed to not move
the cursor. You can make _l_e_s_s think that charac
ters 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.
-s or --squeeze-blank-lines
Causes consecutive blank lines to be squeezed into
a single blank line. This is useful when viewing
_n_r_o_f_f output.
-S or --chop-long-lines
Causes lines longer than the screen width to be
chopped rather than folded. That is, the portion
of a long line that does not fit in the screen
width is not shown. The default is to fold long
lines; that is, display the remainder on the next
line.
-t_t_a_g or --tag=_t_a_g
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 exam
ple, there may be a file in the current directory
called "tags", which was previously built by _c_t_a_g_s
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(1) or an equivalent command. If the environment
variable LESSGLOBALTAGS is set, it is taken to be
the name of a command compatible with _g_l_o_b_a_l (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
_l_e_s_s (using the - command) as a way of examining a
new file. The command ":t" is equivalent to speci
fying -t from within _l_e_s_s_.
-T_t_a_g_s_f_i_l_e or --tag-file=_t_a_g_s_f_i_l_e
Specifies a tags file to be used instead of "tags".
-u or --underline-special
Causes backspaces and carriage returns to be
treated as printable characters; that is, they are
sent to the terminal when they appear in the input.
-U or --UNDERLINE-SPECIAL
Causes backspaces, tabs and carriage returns to be
treated as control characters; that is, they are
handled as specified by the -r option.
By default, if neither -u nor -U is given,
backspaces which appear adjacent to an underscore
character are treated specially: the underlined
text is displayed using the terminal's hardware
underlining capability. Also, backspaces which
appear between two identical characters are treated
specially: the overstruck text is printed using the
terminal's hardware boldface capability. Other
backspaces are deleted, along with the preceding
character. Carriage returns immediately followed
by a newline are deleted. other carriage returns
are handled as specified by the -r option. Text
which is overstruck or underlined can be searched
for if neither -u nor -U is in effect.
-V or --version
Displays the version number of _l_e_s_s_.
-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 high
lights 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
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line after any forward movement command larger than
one line.
-x_n,... or --tabs=_n,...
Sets tab stops. If only one _n is specified, tab
stops are set at multiples of _n. If multiple val
ues separated by commas are specified, tab stops
are set at those positions, and then continue with
the same spacing as the last two. For example,
_-_x_9_,_1_7 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.
--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.
-y_n or --max-forw-scroll=_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 or --window=_n
Changes the default scrolling window size to _n
lines. The default is one screenful. The z and w
commands can also be used to change the window
size. The "z" may be omitted for compatibility
with _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.
-_"_c_c or --quotes=_c_c
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
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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).
-~ or --tilde
Normally lines after end of file are displayed as a
single tilde (~). This option causes lines after
end of file to be displayed as blank lines.
-# or --shift
Specifies the default number of positions to scroll
horizontally in the RIGHTARROW and LEFTARROW com
mands. If the number specified is zero, it sets
the default number of positions to one half of the
screen width.
-- A command line argument of "--" marks the end of
option 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.
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.
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RIGHTARROW [ ESC-l ]
Move the cursor one space to the right.
^LEFTARROW [ ESC-b or ESC-LEFTARROW ]
(That is, CONTROL and LEFTARROW simultaneously.)
Move the cursor one word to the left.
^RIGHTARROW [ ESC-w or ESC-RIGHTARROW ]
(That is, CONTROL and RIGHTARROW simultaneously.)
Move the cursor one word to the right.
HOME [ ESC-0 ]
Move the cursor to the beginning of the line.
END [ ESC-$ ]
Move the cursor to the end of the line.
BACKSPACE
Delete the character to the left of the cursor, or
cancel the command if the command line is empty.
DELETE or [ ESC-x ]
Delete the character under the cursor.
^BACKSPACE [ ESC-BACKSPACE ]
(That is, CONTROL and BACKSPACE simultaneously.)
Delete the word to the left of the cursor.
^DELETE [ ESC-X or ESC-DELETE ]
(That is, CONTROL and DELETE simultaneously.)
Delete the word under the cursor.
UPARROW [ ESC-k ]
Retrieve the previous command line.
DOWNARROW [ ESC-j ]
Retrieve the next command line.
TAB Complete the partial filename to the left of the
cursor. If it matches more than one filename, the
first match is entered into the command line.
Repeated TABs will cycle thru the other matching
filenames. If the completed filename is a 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
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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 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 "$HOME/.less". On
MS-DOS and Windows systems, _l_e_s_s looks for a lesskey file
called "$HOME/_less", and if it is not found there, then
looks for a lesskey file called "_less" in any directory
specified in the PATH environment variable. On OS/2 sys
tems, _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 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 _l_e_s_s_k_e_y 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,
_l_e_s_s uses that as the name of the system-wide lesskey
file. Otherwise, _l_e_s_s looks in a standard place for the
system-wide lesskey file: On Unix systems, the system-wide
lesskey file is /usr/local/etc/sysless. (However, if _l_e_s_s
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.
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
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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
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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.
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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 BS, TAB, NL, CR, and formfeed are control charac
ters, 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 LESS
CHARSET=IBM-1047 or LC_CTYPE=en_US in your environ
ment.
koi8-r Selects a Russian character set.
next Selects a character set appropriate for NeXT com
puters.
utf-8 Selects the UTF-8 encoding of the ISO 10646 charac
ter set.
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:
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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 the
string "UTF-8" 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
_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.
Finally, if the _s_e_t_l_o_c_a_l_e interface is also not available,
the default character set is latin1.
Control and binary characters are displayed in standout
(reverse video). Each such character is displayed in
caret notation if possible (e.g. ^A for control-A). Caret
notation is used only if inverting the 0100 bit results in
a normal printable character. Otherwise, the character is
displayed as a hex number in angle brackets. This format
can be changed by setting the LESSBINFMT environment 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:
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%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.
%c Replaced by the column number of the text appearing
in the first column of the screen.
%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
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, based on byte offsets. The line used is
determined by the _X as with the %b option.
%P_X 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
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anywhere.
%x Replaced by the name of the next input file in the
list.
If any item is unknown (for example, the file size if
input is a pipe), a question mark is printed instead.
The format of the prompt string can be changed depending
on certain conditions. A question mark followed by a 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.
?b_X 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).
?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,
based on byte offsets, of the specified line is
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LESS(1) LESS(1)
known.
?P_X 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 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.
?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) ..?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. .
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LESS(1) LESS(1)
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
-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. 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.
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COLUMNS
Sets the number of columns on the screen. Takes
precedence over the number of columns specified by
the TERM variable. (But if you have a windowing
system which supports TIOCGWINSZ or WIOCGETD, the
window system's idea of the screen size takes
precedence over the LINES and COLUMNS environment
variables.)
EDITOR The name of the editor (used for the v command).
HOME Name of the user's home directory (used to find a
lesskey file on Unix and OS/2 systems).
HOMEDRIVE, HOMEPATH
Concatenation of the HOMEDRIVE and HOMEPATH envi
ronment 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 _l_e_s_s automatically.
LESSANSIENDCHARS
Characters which are assumed to end an ANSI color
escape sequence (default "m").
LESSBINFMT
Format for displaying non-printable, non-control
characters.
LESSCHARDEF
Defines a character set.
LESSCHARSET
Selects a predefined character set.
LESSCLOSE
Command line to invoke the (optional) input-post
processor.
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.
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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 _g_l_o_b_a_l (1) command. If not
set, global tags are not used.
LESSKEY
Name of the default lesskey(1) file.
LESSKEY_SYSTEM
Name of the default system-wide lesskey(1) file.
LESSMETACHARS
List of characters which are considered "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.
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LESS(1) LESS(1)
VISUAL The name of the editor (used for the v command).
SSEEEE AALLSSOO
lesskey(1)
WWAARRNNIINNGGSS
The = command and prompts (unless changed by -P) report
the line numbers of the lines at the top and bottom of the
screen, but the byte and percent of the line after the one
at the bottom of the screen.
If the :e command is used to name more than one file, 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.)
When viewing text containing ANSI color escape sequences
using the -R option, searching will not find text contain
ing an embedded escape sequence. Also, search highlight
ing may change the color of some of the text which follows
the highlighted text.
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).
See http://www.greenwoodsoftware.com/less for the latest
list of known bugs in this version of less.
CCOOPPYYRRIIGGHHTT
Copyright (C) 2002 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
Version 381: 17 Jan 2003 30
LESS(1) LESS(1)
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 war
ranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PUR
POSE. See the GNU General Public License for more
details.
AAUUTTHHOORR
Mark Nudelman <markn@greenwoodsoftware.com>
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 381: 17 Jan 2003 31
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