6 less - opposite of more
12 \e[1mless --version
\e[0m
13 \e[1mless [-[+]aABcCdeEfFgGiIJKLmMnNqQrRsSuUVwWX~]
\e[0m
14 \e[1m[-b
\e[4m
\e[22mspace
\e[24m
\e[1m] [-h
\e[4m
\e[22mlines
\e[24m
\e[1m] [-j
\e[4m
\e[22mline
\e[24m
\e[1m] [-k
\e[4m
\e[22mkeyfile
\e[24m
\e[1m]
\e[0m
15 \e[1m[-{oO}
\e[4m
\e[22mlogfile
\e[24m
\e[1m] [-p
\e[4m
\e[22mpattern
\e[24m
\e[1m] [-P
\e[4m
\e[22mprompt
\e[24m
\e[1m] [-t
\e[4m
\e[22mtag
\e[24m
\e[1m]
\e[0m
16 \e[1m[-T
\e[4m
\e[22mtagsfile
\e[24m
\e[1m] [-x
\e[4m
\e[22mtab
\e[24m
\e[1m,...] [-y
\e[4m
\e[22mlines
\e[24m
\e[1m] [-[z]
\e[4m
\e[22mlines
\e[24m
\e[1m]
\e[0m
17 \e[1m[-#
\e[4m
\e[22mshift
\e[24m
\e[1m] [+[+]
\e[4m
\e[22mcmd
\e[24m
\e[1m] [--] [
\e[4m
\e[22mfilename
\e[24m
\e[1m]...
\e[0m
18 (See the OPTIONS section for alternate option syntax with long option
23 \e[4mLess
\e[24m is a program similar to
\e[4mmore
\e[24m (1), but which allows backward move-
24 ment in the file as well as forward movement. Also,
\e[4mless
\e[24m does not have
25 to read the entire input file before starting, so with large input
26 files it starts up faster than text editors like
\e[4mvi
\e[24m (1).
\e[4mLess
\e[24m uses
27 termcap (or terminfo on some systems), so it can run on a variety of
28 terminals. There is even limited support for hardcopy terminals. (On
29 a hardcopy terminal, lines which should be printed at the top of the
30 screen are prefixed with a caret.)
32 Commands are based on both
\e[4mmore
\e[24m and
\e[4mvi.
\e[24m Commands may be preceded by a
33 decimal number, called N in the descriptions below. The number is used
34 by some commands, as indicated.
38 In the following descriptions, ^X means control-X. ESC stands for the
39 ESCAPE key; for example ESC-v means the two character sequence
42 h or H Help: display a summary of these commands. If you forget all
43 the other commands, remember this one.
45 SPACE or ^V or f or ^F
46 Scroll forward N lines, default one window (see option -z
47 below). If N is more than the screen size, only the final
48 screenful is displayed. Warning: some systems use ^V as a spe-
49 cial literalization character.
51 z Like SPACE, but if N is specified, it becomes the new window
55 Like SPACE, but scrolls a full screenful, even if it reaches
56 end-of-file in the process.
58 ENTER or RETURN or ^N or e or ^E or j or ^J
59 Scroll forward N lines, default 1. The entire N lines are dis-
60 played, even if N is more than the screen size.
63 Scroll forward N lines, default one half of the screen size. If
64 N is specified, it becomes the new default for subsequent d and
68 Scroll backward N lines, default one window (see option -z
69 below). If N is more than the screen size, only the final
70 screenful is displayed.
72 w Like ESC-v, but if N is specified, it becomes the new window
75 y or ^Y or ^P or k or ^K
76 Scroll backward N lines, default 1. The entire N lines are dis-
77 played, even if N is more than the screen size. Warning: some
78 systems use ^Y as a special job control character.
81 Scroll backward N lines, default one half of the screen size.
82 If N is specified, it becomes the new default for subsequent d
86 Scroll horizontally right N characters, default half the screen
87 width (see the -# option). If a number N is specified, it
88 becomes the default for future RIGHTARROW and LEFTARROW com-
89 mands. While the text is scrolled, it acts as though the -S
90 option (chop lines) were in effect.
93 Scroll horizontally left N characters, default half the screen
94 width (see the -# option). If a number N is specified, it
95 becomes the default for future RIGHTARROW and LEFTARROW com-
101 R Repaint the screen, discarding any buffered input. Useful if
102 the file is changing while it is being viewed.
104 F Scroll forward, and keep trying to read when the end of file is
105 reached. Normally this command would be used when already at
106 the end of the file. It is a way to monitor the tail of a file
107 which is growing while it is being viewed. (The behavior is
108 similar to the "tail -f" command.)
110 ESC-F Like F, but as soon as a line is found which matches the last
111 search pattern, the terminal bell is rung and forward scrolling
115 Go to line N in the file, default 1 (beginning of file). (Warn-
116 ing: this may be slow if N is large.)
119 Go to line N in the file, default the end of the file. (Warn-
120 ing: this may be slow if N is large, or if N is not specified
121 and standard input, rather than a file, is being read.)
123 p or % Go to a position N percent into the file. N should be between 0
124 and 100, and may contain a decimal point.
126 P Go to the line containing byte offset N in the file.
128 { If a left curly bracket appears in the top line displayed on the
129 screen, the { command will go to the matching right curly
130 bracket. The matching right curly bracket is positioned on the
131 bottom line of the screen. If there is more than one left curly
132 bracket on the top line, a number N may be used to specify the
133 N-th bracket on the line.
135 } If a right curly bracket appears in the bottom line displayed on
136 the screen, the } command will go to the matching left curly
137 bracket. The matching left curly bracket is positioned on the
138 top line of the screen. If there is more than one right curly
139 bracket on the top line, a number N may be used to specify the
140 N-th bracket on the line.
142 ( Like {, but applies to parentheses rather than curly brackets.
144 ) Like }, but applies to parentheses rather than curly brackets.
146 [ Like {, but applies to square brackets rather than curly brack-
149 ] Like }, but applies to square brackets rather than curly brack-
152 ESC-^F Followed by two characters, acts like {, but uses the two char-
153 acters as open and close brackets, respectively. For example,
154 "ESC ^F < >" could be used to go forward to the > which matches
155 the < in the top displayed line.
157 ESC-^B Followed by two characters, acts like }, but uses the two char-
158 acters as open and close brackets, respectively. For example,
159 "ESC ^B < >" could be used to go backward to the < which matches
160 the > in the bottom displayed line.
162 m Followed by any lowercase letter, marks the current position
165 ' (Single quote.) Followed by any lowercase letter, returns to
166 the position which was previously marked with that letter. Fol-
167 lowed by another single quote, returns to the position at which
168 the last "large" movement command was executed. Followed by a ^
169 or $, jumps to the beginning or end of the file respectively.
170 Marks are preserved when a new file is examined, so the ' com-
171 mand can be used to switch between input files.
173 ^X^X Same as single quote.
176 Search forward in the file for the N-th line containing the pat-
177 tern. N defaults to 1. The pattern is a regular expression, as
178 recognized by the regular expression library supplied by your
179 system. The search starts at the first line displayed (but see
180 the -a and -j options, which change this).
182 Certain characters are special if entered at the beginning of
183 the pattern; they modify the type of search rather than become
187 Search for lines which do NOT match the pattern.
190 Search multiple files. That is, if the search reaches
191 the END of the current file without finding a match, the
192 search continues in the next file in the command line
196 Begin the search at the first line of the FIRST file in
197 the command line list, regardless of what is currently
198 displayed on the screen or the settings of the -a or -j
201 ^K Highlight any text which matches the pattern on the cur-
202 rent screen, but don't move to the first match (KEEP cur-
205 ^R Don't interpret regular expression metacharacters; that
206 is, do a simple textual comparison.
209 Search backward in the file for the N-th line containing the
210 pattern. The search starts at the line immediately before the
213 Certain characters are special as in the / command:
216 Search for lines which do NOT match the pattern.
219 Search multiple files. That is, if the search reaches
220 the beginning of the current file without finding a
221 match, the search continues in the previous file in the
225 Begin the search at the last line of the last file in the
226 command line list, regardless of what is currently dis-
227 played on the screen or the settings of the -a or -j
230 ^K As in forward searches.
232 ^R As in forward searches.
240 n Repeat previous search, for N-th line containing the last pat-
241 tern. If the previous search was modified by ^N, the search is
242 made for the N-th line NOT containing the pattern. If the pre-
243 vious search was modified by ^E, the search continues in the
244 next (or previous) file if not satisfied in the current file.
245 If the previous search was modified by ^R, the search is done
246 without using regular expressions. There is no effect if the
247 previous search was modified by ^F or ^K.
249 N Repeat previous search, but in the reverse direction.
251 ESC-n Repeat previous search, but crossing file boundaries. The
252 effect is as if the previous search were modified by *.
254 ESC-N Repeat previous search, but in the reverse direction and cross-
257 ESC-u Undo search highlighting. Turn off highlighting of strings
258 matching the current search pattern. If highlighting is already
259 off because of a previous ESC-u command, turn highlighting back
260 on. Any search command will also turn highlighting back on.
261 (Highlighting can also be disabled by toggling the -G option; in
262 that case search commands do not turn highlighting back on.)
265 Display only lines which match the pattern; lines which do not
266 match the pattern are not displayed. If pattern is empty (if
267 you type & immediately followed by ENTER), any filtering is
268 turned off, and all lines are displayed. While filtering is in
269 effect, an ampersand is displayed at the beginning of the
270 prompt, as a reminder that some lines in the file may be hidden.
272 Certain characters are special as in the / command:
275 Display only lines which do NOT match the pattern.
277 ^R Don't interpret regular expression metacharacters; that
278 is, do a simple textual comparison.
281 Examine a new file. If the filename is missing, the "current"
282 file (see the :n and :p commands below) from the list of files
283 in the command line is re-examined. A percent sign (%) in the
284 filename is replaced by the name of the current file. A pound
285 sign (#) is replaced by the name of the previously examined
286 file. However, two consecutive percent signs are simply
287 replaced with a single percent sign. This allows you to enter a
288 filename that contains a percent sign in the name. Similarly,
289 two consecutive pound signs are replaced with a single pound
290 sign. The filename is inserted into the command line list of
291 files so that it can be seen by subsequent :n and :p commands.
292 If the filename consists of several files, they are all inserted
293 into the list of files and the first one is examined. If the
294 filename contains one or more spaces, the entire filename should
295 be enclosed in double quotes (also see the -" option).
298 Same as :e. Warning: some systems use ^V as a special literal-
299 ization character. On such systems, you may not be able to use
302 :n Examine the next file (from the list of files given in the com-
303 mand line). If a number N is specified, the N-th next file is
306 :p Examine the previous file in the command line list. If a number
307 N is specified, the N-th previous file is examined.
309 :x Examine the first file in the command line list. If a number N
310 is specified, the N-th file in the list is examined.
312 :d Remove the current file from the list of files.
314 t Go to the next tag, if there were more than one matches for the
315 current tag. See the -t option for more details about tags.
317 T Go to the previous tag, if there were more than one matches for
321 Prints some information about the file being viewed, including
322 its name and the line number and byte offset of the bottom line
323 being displayed. If possible, it also prints the length of the
324 file, the number of lines in the file and the percent of the
325 file above the last displayed line.
327 - Followed by one of the command line option letters (see OPTIONS
328 below), this will change the setting of that option and print a
329 message describing the new setting. If a ^P (CONTROL-P) is
330 entered immediately after the dash, the setting of the option is
331 changed but no message is printed. If the option letter has a
332 numeric value (such as -b or -h), or a string value (such as -P
333 or -t), a new value may be entered after the option letter. If
334 no new value is entered, a message describing the current set-
335 ting is printed and nothing is changed.
337 -- Like the - command, but takes a long option name (see OPTIONS
338 below) rather than a single option letter. You must press ENTER
339 or RETURN after typing the option name. A ^P immediately after
340 the second dash suppresses printing of a message describing the
341 new setting, as in the - command.
343 -+ Followed by one of the command line option letters this will
344 reset the option to its default setting and print a message
345 describing the new setting. (The "-+
\e[4mX
\e[24m" command does the same
346 thing as "-+
\e[4mX
\e[24m" on the command line.) This does not work for
347 string-valued options.
349 --+ Like the -+ command, but takes a long option name rather than a
350 single option letter.
352 -! Followed by one of the command line option letters, this will
353 reset the option to the "opposite" of its default setting and
354 print a message describing the new setting. This does not work
355 for numeric or string-valued options.
357 --! Like the -! command, but takes a long option name rather than a
358 single option letter.
360 _ (Underscore.) Followed by one of the command line option let-
361 ters, this will print a message describing the current setting
362 of that option. The setting of the option is not changed.
364 __ (Double underscore.) Like the _ (underscore) command, but takes
365 a long option name rather than a single option letter. You must
366 press ENTER or RETURN after typing the option name.
368 +cmd Causes the specified cmd to be executed each time a new file is
369 examined. For example, +G causes
\e[4mless
\e[24m to initially display each
370 file starting at the end rather than the beginning.
372 V Prints the version number of
\e[4mless
\e[24m being run.
374 q or Q or :q or :Q or ZZ
375 Exits
\e[4mless.
\e[0m
377 The following four commands may or may not be valid, depending on your
378 particular installation.
380 v Invokes an editor to edit the current file being viewed. The
381 editor is taken from the environment variable VISUAL if defined,
382 or EDITOR if VISUAL is not defined, or defaults to "vi" if nei-
383 ther VISUAL nor EDITOR is defined. See also the discussion of
384 LESSEDIT under the section on PROMPTS below.
387 Invokes a shell to run the shell-command given. A percent sign
388 (%) in the command is replaced by the name of the current file.
389 A pound sign (#) is replaced by the name of the previously exam-
390 ined file. "!!" repeats the last shell command. "!" with no
391 shell command simply invokes a shell. On Unix systems, the
392 shell is taken from the environment variable SHELL, or defaults
393 to "sh". On MS-DOS and OS/2 systems, the shell is the normal
397 <m> represents any mark letter. Pipes a section of the input
398 file to the given shell command. The section of the file to be
399 piped is between the first line on the current screen and the
400 position marked by the letter. <m> may also be ^ or $ to indi-
401 cate beginning or end of file respectively. If <m> is . or new-
402 line, the current screen is piped.
405 Save the input to a file. This only works if the input is a
406 pipe, not an ordinary file.
409 Command line options are described below. Most options may be changed
410 while
\e[4mless
\e[24m is running, via the "-" command.
412 Most options may be given in one of two forms: either a dash followed
413 by a single letter, or two dashes followed by a long option name. A
414 long option name may be abbreviated as long as the abbreviation is
415 unambiguous. For example, --quit-at-eof may be abbreviated --quit, but
416 not --qui, since both --quit-at-eof and --quiet begin with --qui. Some
417 long option names are in uppercase, such as --QUIT-AT-EOF, as distinct
418 from --quit-at-eof. Such option names need only have their first let-
419 ter capitalized; the remainder of the name may be in either case. For
420 example, --Quit-at-eof is equivalent to --QUIT-AT-EOF.
422 Options are also taken from the environment variable "LESS". For exam-
423 ple, to avoid typing "less -options ..." each time
\e[4mless
\e[24m is invoked, you
424 might tell
\e[4mcsh:
\e[0m
426 setenv LESS "-options"
428 or if you use
\e[4msh:
\e[0m
430 LESS="-options"; export LESS
432 On MS-DOS, you don't need the quotes, but you should replace any per-
433 cent signs in the options string by double percent signs.
435 The environment variable is parsed before the command line, so command
436 line options override the LESS environment variable. If an option
437 appears in the LESS variable, it can be reset to its default value on
438 the command line by beginning the command line option with "-+".
440 Some options like -k or -D require a string to follow the option let-
441 ter. The string for that option is considered to end when a dollar
442 sign ($) is found. For example, you can set two -D options on MS-DOS
447 If the --use-backslash option appears earlier in the options, then a
448 dollar sign or backslash may be included literally in an option string
449 by preceding it with a backslash. If the --use-backslash option is not
450 in effect, then backslashes are not treated specially, and there is no
451 way to include a dollar sign in the option string.
454 This option displays a summary of the commands accepted by
\e[4mless
\e[0m
455 (the same as the h command). (Depending on how your shell
456 interprets the question mark, it may be necessary to quote the
457 question mark, thus: "-\?".)
459 -a or --search-skip-screen
460 By default, forward searches start at the top of the displayed
461 screen and backwards searches start at the bottom of the dis-
462 played screen (except for repeated searches invoked by the n or
463 N commands, which start after or before the "target" line
464 respectively; see the -j option for more about the target line).
465 The -a option causes forward searches to instead start at the
466 bottom of the screen and backward searches to start at the top
467 of the screen, thus skipping all lines displayed on the screen.
469 -A or --SEARCH-SKIP-SCREEN
470 Causes all forward searches (not just non-repeated searches) to
471 start just after the target line, and all backward searches to
472 start just before the target line. Thus, forward searches will
473 skip part of the displayed screen (from the first line up to and
474 including the target line). Similarly backwards searches will
475 skip the displayed screen from the last line up to and including
476 the target line. This was the default behavior in less versions
479 -b
\e[4mn
\e[24m or --buffers=
\e[4mn
\e[0m
480 Specifies the amount of buffer space
\e[4mless
\e[24m will use for each
481 file, in units of kilobytes (1024 bytes). By default 64K of
482 buffer space is used for each file (unless the file is a pipe;
483 see the -B option). The -b option specifies instead that
\e[4mn
\e[0m
484 kilobytes of buffer space should be used for each file. If
\e[4mn
\e[24m is
485 -1, buffer space is unlimited; that is, the entire file can be
489 By default, when data is read from a pipe, buffers are allocated
490 automatically as needed. If a large amount of data is read from
491 the pipe, this can cause a large amount of memory to be allo-
492 cated. The -B option disables this automatic allocation of buf-
493 fers for pipes, so that only 64K (or the amount of space speci-
494 fied by the -b option) is used for the pipe. Warning: use of -B
495 can result in erroneous display, since only the most recently
496 viewed part of the piped data is kept in memory; any earlier
500 Causes full screen repaints to be painted from the top line
501 down. By default, full screen repaints are done by scrolling
502 from the bottom of the screen.
505 Same as -c, for compatibility with older versions of
\e[4mless.
\e[0m
508 The -d option suppresses the error message normally displayed if
509 the terminal is dumb; that is, lacks some important capability,
510 such as the ability to clear the screen or scroll backward. The
511 -d option does not otherwise change the behavior of
\e[4mless
\e[24m on a
514 -D
\e[1mx
\e[4m
\e[22mcolor
\e[24m or --color=
\e[1mx
\e[4m
\e[22mcolor
\e[0m
515 [MS-DOS only] Sets the color of the text displayed.
\e[1mx
\e[22mis a sin-
516 gle character which selects the type of text whose color is
517 being set: n=normal, s=standout, d=bold, u=underlined, k=blink.
518 \e[4mcolor
\e[24m is a pair of numbers separated by a period. The first
519 number selects the foreground color and the second selects the
520 background color of the text. A single number
\e[4mN
\e[24m is the same as
521 \e[4mN.M
\e[24m, where
\e[4mM
\e[24m is the normal background color.
525 Causes
\e[4mless
\e[24m to automatically exit the second time it reaches
526 end-of-file. By default, the only way to exit
\e[4mless
\e[24m is via the
530 Causes
\e[4mless
\e[24m to automatically exit the first time it reaches end-
534 Forces non-regular files to be opened. (A non-regular file is a
535 directory or a device special file.) Also suppresses the warn-
536 ing message when a binary file is opened. By default,
\e[4mless
\e[24m will
537 refuse to open non-regular files. Note that some operating sys-
538 tems will not allow directories to be read, even if -f is set.
540 -F or --quit-if-one-screen
541 Causes
\e[4mless
\e[24m to automatically exit if the entire file can be dis-
542 played on the first screen.
544 -g or --hilite-search
545 Normally,
\e[4mless
\e[24m will highlight ALL strings which match the last
546 search command. The -g option changes this behavior to high-
547 light only the particular string which was found by the last
548 search command. This can cause
\e[4mless
\e[24m to run somewhat faster than
551 -G or --HILITE-SEARCH
552 The -G option suppresses all highlighting of strings found by
555 -h
\e[4mn
\e[24m or --max-back-scroll=
\e[4mn
\e[0m
556 Specifies a maximum number of lines to scroll backward. If it
557 is necessary to scroll backward more than
\e[4mn
\e[24m lines, the screen is
558 repainted in a forward direction instead. (If the terminal does
559 not have the ability to scroll backward, -h0 is implied.)
562 Causes searches to ignore case; that is, uppercase and lowercase
563 are considered identical. This option is ignored if any upper-
564 case letters appear in the search pattern; in other words, if a
565 pattern contains uppercase letters, then that search does not
569 Like -i, but searches ignore case even if the pattern contains
572 -j
\e[4mn
\e[24m or --jump-target=
\e[4mn
\e[0m
573 Specifies a line on the screen where the "target" line is to be
574 positioned. The target line is the line specified by any com-
575 mand to search for a pattern, jump to a line number, jump to a
576 file percentage or jump to a tag. The screen line may be speci-
577 fied by a number: the top line on the screen is 1, the next is
578 2, and so on. The number may be negative to specify a line rel-
579 ative to the bottom of the screen: the bottom line on the screen
580 is -1, the second to the bottom is -2, and so on. Alternately,
581 the screen line may be specified as a fraction of the height of
582 the screen, starting with a decimal point: .5 is in the middle
583 of the screen, .3 is three tenths down from the first line, and
584 so on. If the line is specified as a fraction, the actual line
585 number is recalculated if the terminal window is resized, so
586 that the target line remains at the specified fraction of the
587 screen height. If any form of the -j option is used, forward
588 searches begin at the line immediately after the target line,
589 and backward searches begin at the target line, unless changed
590 by -a or -A. For example, if "-j4" is used, the target line is
591 the fourth line on the screen, so forward searches begin at the
592 fifth line on the screen.
594 -J or --status-column
595 Displays a status column at the left edge of the screen. The
596 status column shows the lines that matched the current search.
597 The status column is also used if the -w or -W option is in
600 -k
\e[4mfilename
\e[24m or --lesskey-file=
\e[4mfilename
\e[0m
601 Causes
\e[4mless
\e[24m to open and interpret the named file as a
\e[4mlesskey
\e[0m
602 (1) file. Multiple -k options may be specified. If the LESSKEY
603 or LESSKEY_SYSTEM environment variable is set, or if a lesskey
604 file is found in a standard place (see KEY BINDINGS), it is also
605 used as a
\e[4mlesskey
\e[24m file.
608 Causes
\e[4mless
\e[24m to exit immediately (with status 2) when an inter-
609 rupt character (usually ^C) is typed. Normally, an interrupt
610 character causes
\e[4mless
\e[24m to stop whatever it is doing and return to
611 its command prompt. Note that use of this option makes it
612 impossible to return to the command prompt from the "F" command.
615 Ignore the LESSOPEN environment variable (see the INPUT PRE-
616 PROCESSOR section below). This option can be set from within
617 \e[4mless
\e[24m, but it will apply only to files opened subsequently, not
618 to the file which is currently open.
621 Causes
\e[4mless
\e[24m to prompt verbosely (like
\e[4mmore
\e[24m), with the percent
622 into the file. By default,
\e[4mless
\e[24m prompts with a colon.
625 Causes
\e[4mless
\e[24m to prompt even more verbosely than
\e[4mmore.
\e[0m
628 Suppresses line numbers. The default (to use line numbers) may
629 cause
\e[4mless
\e[24m to run more slowly in some cases, especially with a
630 very large input file. Suppressing line numbers with the -n
631 option will avoid this problem. Using line numbers means: the
632 line number will be displayed in the verbose prompt and in the =
633 command, and the v command will pass the current line number to
634 the editor (see also the discussion of LESSEDIT in PROMPTS
638 Causes a line number to be displayed at the beginning of each
641 -o
\e[4mfilename
\e[24m or --log-file=
\e[4mfilename
\e[0m
642 Causes
\e[4mless
\e[24m to copy its input to the named file as it is being
643 viewed. This applies only when the input file is a pipe, not an
644 ordinary file. If the file already exists,
\e[4mless
\e[24m will ask for
645 confirmation before overwriting it.
647 -O
\e[4mfilename
\e[24m or --LOG-FILE=
\e[4mfilename
\e[0m
648 The -O option is like -o, but it will overwrite an existing file
649 without asking for confirmation.
651 If no log file has been specified, the -o and -O options can be
652 used from within
\e[4mless
\e[24m to specify a log file. Without a file
653 name, they will simply report the name of the log file. The "s"
654 command is equivalent to specifying -o from within
\e[4mless.
\e[0m
656 -p
\e[4mpattern
\e[24m or --pattern=
\e[4mpattern
\e[0m
657 The -p option on the command line is equivalent to specifying
658 +/
\e[4mpattern
\e[24m; that is, it tells
\e[4mless
\e[24m to start at the first occur-
659 rence of
\e[4mpattern
\e[24m in the file.
661 -P
\e[4mprompt
\e[24m or --prompt=
\e[4mprompt
\e[0m
662 Provides a way to tailor the three prompt styles to your own
663 preference. This option would normally be put in the LESS envi-
664 ronment variable, rather than being typed in with each
\e[4mless
\e[24m com-
665 mand. Such an option must either be the last option in the LESS
666 variable, or be terminated by a dollar sign. -Ps followed by a
667 string changes the default (short) prompt to that string. -Pm
668 changes the medium (-m) prompt. -PM changes the long (-M)
669 prompt. -Ph changes the prompt for the help screen. -P=
670 changes the message printed by the = command. -Pw changes the
671 message printed while waiting for data (in the F command). All
672 prompt strings consist of a sequence of letters and special
673 escape sequences. See the section on PROMPTS for more details.
675 -q or --quiet or --silent
676 Causes moderately "quiet" operation: the terminal bell is not
677 rung if an attempt is made to scroll past the end of the file or
678 before the beginning of the file. If the terminal has a "visual
679 bell", it is used instead. The bell will be rung on certain
680 other errors, such as typing an invalid character. The default
681 is to ring the terminal bell in all such cases.
683 -Q or --QUIET or --SILENT
684 Causes totally "quiet" operation: the terminal bell is never
687 -r or --raw-control-chars
688 Causes "raw" control characters to be displayed. The default is
689 to display control characters using the caret notation; for
690 example, a control-A (octal 001) is displayed as "^A". Warning:
691 when the -r option is used,
\e[4mless
\e[24m cannot keep track of the actual
692 appearance of the screen (since this depends on how the screen
693 responds to each type of control character). Thus, various dis-
694 play problems may result, such as long lines being split in the
697 -R or --RAW-CONTROL-CHARS
698 Like -r, but only ANSI "color" escape sequences are output in
699 "raw" form. Unlike -r, the screen appearance is maintained cor-
700 rectly in most cases. ANSI "color" escape sequences are
701 sequences of the form:
705 where the "..." is zero or more color specification characters
706 For the purpose of keeping track of screen appearance, ANSI
707 color escape sequences are assumed to not move the cursor. You
708 can make
\e[4mless
\e[24m think that characters other than "m" can end ANSI
709 color escape sequences by setting the environment variable
710 LESSANSIENDCHARS to the list of characters which can end a color
711 escape sequence. And you can make
\e[4mless
\e[24m think that characters
712 other than the standard ones may appear between the ESC and the
713 m by setting the environment variable LESSANSIMIDCHARS to the
714 list of characters which can appear.
716 -s or --squeeze-blank-lines
717 Causes consecutive blank lines to be squeezed into a single
718 blank line. This is useful when viewing
\e[4mnroff
\e[24m output.
720 -S or --chop-long-lines
721 Causes lines longer than the screen width to be chopped (trun-
722 cated) rather than wrapped. That is, the portion of a long line
723 that does not fit in the screen width is not shown. The default
724 is to wrap long lines; that is, display the remainder on the
727 -t
\e[4mtag
\e[24m or --tag=
\e[4mtag
\e[0m
728 The -t option, followed immediately by a TAG, will edit the file
729 containing that tag. For this to work, tag information must be
730 available; for example, there may be a file in the current
731 directory called "tags", which was previously built by
\e[4mctags
\e[24m (1)
732 or an equivalent command. If the environment variable LESSGLOB-
733 ALTAGS is set, it is taken to be the name of a command compati-
734 ble with
\e[4mglobal
\e[24m (1), and that command is executed to find the
735 tag. (See http://www.gnu.org/software/global/global.html). The
736 -t option may also be specified from within
\e[4mless
\e[24m (using the -
737 command) as a way of examining a new file. The command ":t" is
738 equivalent to specifying -t from within
\e[4mless.
\e[0m
740 -T
\e[4mtagsfile
\e[24m or --tag-file=
\e[4mtagsfile
\e[0m
741 Specifies a tags file to be used instead of "tags".
743 -u or --underline-special
744 Causes backspaces and carriage returns to be treated as print-
745 able characters; that is, they are sent to the terminal when
746 they appear in the input.
748 -U or --UNDERLINE-SPECIAL
749 Causes backspaces, tabs and carriage returns to be treated as
750 control characters; that is, they are handled as specified by
753 By default, if neither -u nor -U is given, backspaces which
754 appear adjacent to an underscore character are treated spe-
755 cially: the underlined text is displayed using the terminal's
756 hardware underlining capability. Also, backspaces which appear
757 between two identical characters are treated specially: the
758 overstruck text is printed using the terminal's hardware bold-
759 face capability. Other backspaces are deleted, along with the
760 preceding character. Carriage returns immediately followed by a
761 newline are deleted. Other carriage returns are handled as
762 specified by the -r option. Text which is overstruck or under-
763 lined can be searched for if neither -u nor -U is in effect.
766 Displays the version number of
\e[4mless.
\e[0m
768 -w or --hilite-unread
769 Temporarily highlights the first "new" line after a forward
770 movement of a full page. The first "new" line is the line imme-
771 diately following the line previously at the bottom of the
772 screen. Also highlights the target line after a g or p command.
773 The highlight is removed at the next command which causes move-
774 ment. The entire line is highlighted, unless the -J option is
775 in effect, in which case only the status column is highlighted.
777 -W or --HILITE-UNREAD
778 Like -w, but temporarily highlights the first new line after any
779 forward movement command larger than one line.
781 -x
\e[4mn
\e[24m,... or --tabs=
\e[4mn
\e[24m,...
782 Sets tab stops. If only one
\e[4mn
\e[24m is specified, tab stops are set
783 at multiples of
\e[4mn
\e[24m. If multiple values separated by commas are
784 specified, tab stops are set at those positions, and then con-
785 tinue with the same spacing as the last two. For example,
786 \e[4m-x9,17
\e[24m will set tabs at positions 9, 17, 25, 33, etc. The
787 default for
\e[4mn
\e[24m is 8.
790 Disables sending the termcap initialization and deinitialization
791 strings to the terminal. This is sometimes desirable if the
792 deinitialization string does something unnecessary, like clear-
795 -y
\e[4mn
\e[24m or --max-forw-scroll=
\e[4mn
\e[0m
796 Specifies a maximum number of lines to scroll forward. If it is
797 necessary to scroll forward more than
\e[4mn
\e[24m lines, the screen is
798 repainted instead. The -c or -C option may be used to repaint
799 from the top of the screen if desired. By default, any forward
800 movement causes scrolling.
802 -[z]
\e[4mn
\e[24m or --window=
\e[4mn
\e[0m
803 Changes the default scrolling window size to
\e[4mn
\e[24m lines. The
804 default is one screenful. The z and w commands can also be used
805 to change the window size. The "z" may be omitted for compati-
806 bility with some versions of
\e[4mmore.
\e[24m If the number
\e[4mn
\e[24m is negative,
807 it indicates
\e[4mn
\e[24m lines less than the current screen size. For
808 example, if the screen is 24 lines,
\e[4m-z-4
\e[24m sets the scrolling win-
809 dow to 20 lines. If the screen is resized to 40 lines, the
810 scrolling window automatically changes to 36 lines.
812 -
\e[4m"cc
\e[24m or --quotes=
\e[4mcc
\e[0m
813 Changes the filename quoting character. This may be necessary
814 if you are trying to name a file which contains both spaces and
815 quote characters. Followed by a single character, this changes
816 the quote character to that character. Filenames containing a
817 space should then be surrounded by that character rather than by
818 double quotes. Followed by two characters, changes the open
819 quote to the first character, and the close quote to the second
820 character. Filenames containing a space should then be preceded
821 by the open quote character and followed by the close quote
822 character. Note that even after the quote characters are
823 changed, this option remains -" (a dash followed by a double
827 Normally lines after end of file are displayed as a single tilde
828 (~). This option causes lines after end of file to be displayed
832 Specifies the default number of positions to scroll horizontally
833 in the RIGHTARROW and LEFTARROW commands. If the number speci-
834 fied is zero, it sets the default number of positions to one
835 half of the screen width. Alternately, the number may be speci-
836 fied as a fraction of the width of the screen, starting with a
837 decimal point: .5 is half of the screen width, .3 is three
838 tenths of the screen width, and so on. If the number is speci-
839 fied as a fraction, the actual number of scroll positions is
840 recalculated if the terminal window is resized, so that the
841 actual scroll remains at the specified fraction of the screen
845 Normally, if the input file is renamed while an F command is
846 executing,
\e[4mless
\e[24m will continue to display the contents of the
847 original file despite its name change. If --follow-name is
848 specified, during an F command
\e[4mless
\e[24m will periodically attempt to
849 reopen the file by name. If the reopen succeeds and the file is
850 a different file from the original (which means that a new file
851 has been created with the same name as the original (now
852 renamed) file),
\e[4mless
\e[24m will display the contents of that new file.
855 Disables sending the keypad initialization and deinitialization
856 strings to the terminal. This is sometimes useful if the keypad
857 strings make the numeric keypad behave in an undesirable manner.
860 This option changes the interpretations of options which follow
861 this one. After the --use-backslash option, any backslash in an
862 option string is removed and the following character is taken
863 literally. This allows a dollar sign to be included in option
866 -- A command line argument of "--" marks the end of option argu-
867 ments. Any arguments following this are interpreted as file-
868 names. This can be useful when viewing a file whose name begins
871 + If a command line option begins with
\e[1m+
\e[22m, the remainder of that
872 option is taken to be an initial command to
\e[4mless.
\e[24m For example,
873 +G tells
\e[4mless
\e[24m to start at the end of the file rather than the
874 beginning, and +/xyz tells it to start at the first occurrence
875 of "xyz" in the file. As a special case, +<number> acts like
876 +<number>g; that is, it starts the display at the specified line
877 number (however, see the caveat under the "g" command above).
878 If the option starts with ++, the initial command applies to
879 every file being viewed, not just the first one. The + command
880 described previously may also be used to set (or change) an ini-
881 tial command for every file.
884 \e[1mLINE EDITING
\e[0m
885 When entering command line at the bottom of the screen (for example, a
886 filename for the :e command, or the pattern for a search command), cer-
887 tain keys can be used to manipulate the command line. Most commands
888 have an alternate form in [ brackets ] which can be used if a key does
889 not exist on a particular keyboard. (Note that the forms beginning
890 with ESC do not work in some MS-DOS and Windows systems because ESC is
891 the line erase character.) Any of these special keys may be entered
892 literally by preceding it with the "literal" character, either ^V or
893 ^A. A backslash itself may also be entered literally by entering two
897 Move the cursor one space to the left.
900 Move the cursor one space to the right.
902 ^LEFTARROW [ ESC-b or ESC-LEFTARROW ]
903 (That is, CONTROL and LEFTARROW simultaneously.) Move the cur-
904 sor one word to the left.
906 ^RIGHTARROW [ ESC-w or ESC-RIGHTARROW ]
907 (That is, CONTROL and RIGHTARROW simultaneously.) Move the cur-
908 sor one word to the right.
911 Move the cursor to the beginning of the line.
914 Move the cursor to the end of the line.
917 Delete the character to the left of the cursor, or cancel the
918 command if the command line is empty.
921 Delete the character under the cursor.
923 ^BACKSPACE [ ESC-BACKSPACE ]
924 (That is, CONTROL and BACKSPACE simultaneously.) Delete the
925 word to the left of the cursor.
927 ^DELETE [ ESC-X or ESC-DELETE ]
928 (That is, CONTROL and DELETE simultaneously.) Delete the word
932 Retrieve the previous command line. If you first enter some
933 text and then press UPARROW, it will retrieve the previous com-
934 mand which begins with that text.
937 Retrieve the next command line. If you first enter some text
938 and then press DOWNARROW, it will retrieve the next command
939 which begins with that text.
941 TAB Complete the partial filename to the left of the cursor. If it
942 matches more than one filename, the first match is entered into
943 the command line. Repeated TABs will cycle thru the other
944 matching filenames. If the completed filename is a directory, a
945 "/" is appended to the filename. (On MS-DOS systems, a "\" is
946 appended.) The environment variable LESSSEPARATOR can be used
947 to specify a different character to append to a directory name.
950 Like, TAB, but cycles in the reverse direction thru the matching
953 ^L Complete the partial filename to the left of the cursor. If it
954 matches more than one filename, all matches are entered into the
955 command line (if they fit).
957 ^U (Unix and OS/2) or ESC (MS-DOS)
958 Delete the entire command line, or cancel the command if the
959 command line is empty. If you have changed your line-kill char-
960 acter in Unix to something other than ^U, that character is used
963 ^G Delete the entire command line and return to the main prompt.
966 \e[1mKEY BINDINGS
\e[0m
967 You may define your own
\e[4mless
\e[24m commands by using the program
\e[4mlesskey
\e[24m (1)
968 to create a lesskey file. This file specifies a set of command keys
969 and an action associated with each key. You may also use
\e[4mlesskey
\e[24m to
970 change the line-editing keys (see LINE EDITING), and to set environment
971 variables. If the environment variable LESSKEY is set,
\e[4mless
\e[24m uses that
972 as the name of the lesskey file. Otherwise,
\e[4mless
\e[24m looks in a standard
973 place for the lesskey file: On Unix systems,
\e[4mless
\e[24m looks for a lesskey
974 file called "$HOME/.less". On MS-DOS and Windows systems,
\e[4mless
\e[24m looks
975 for a lesskey file called "$HOME/_less", and if it is not found there,
976 then looks for a lesskey file called "_less" in any directory specified
977 in the PATH environment variable. On OS/2 systems,
\e[4mless
\e[24m looks for a
978 lesskey file called "$HOME/less.ini", and if it is not found, then
979 looks for a lesskey file called "less.ini" in any directory specified
980 in the INIT environment variable, and if it not found there, then looks
981 for a lesskey file called "less.ini" in any directory specified in the
982 PATH environment variable. See the
\e[4mlesskey
\e[24m manual page for more
985 A system-wide lesskey file may also be set up to provide key bindings.
986 If a key is defined in both a local lesskey file and in the system-wide
987 file, key bindings in the local file take precedence over those in the
988 system-wide file. If the environment variable LESSKEY_SYSTEM is set,
989 \e[4mless
\e[24m uses that as the name of the system-wide lesskey file. Otherwise,
990 \e[4mless
\e[24m looks in a standard place for the system-wide lesskey file: On
991 Unix systems, the system-wide lesskey file is /usr/local/etc/sysless.
992 (However, if
\e[4mless
\e[24m was built with a different sysconf directory than
993 /usr/local/etc, that directory is where the sysless file is found.) On
994 MS-DOS and Windows systems, the system-wide lesskey file is c:\_sys-
995 less. On OS/2 systems, the system-wide lesskey file is c:\sysless.ini.
998 \e[1mINPUT PREPROCESSOR
\e[0m
999 You may define an "input preprocessor" for
\e[4mless.
\e[24m Before
\e[4mless
\e[24m opens a
1000 file, it first gives your input preprocessor a chance to modify the way
1001 the contents of the file are displayed. An input preprocessor is sim-
1002 ply an executable program (or shell script), which writes the contents
1003 of the file to a different file, called the replacement file. The con-
1004 tents of the replacement file are then displayed in place of the con-
1005 tents of the original file. However, it will appear to the user as if
1006 the original file is opened; that is,
\e[4mless
\e[24m will display the original
1007 filename as the name of the current file.
1009 An input preprocessor receives one command line argument, the original
1010 filename, as entered by the user. It should create the replacement
1011 file, and when finished, print the name of the replacement file to its
1012 standard output. If the input preprocessor does not output a replace-
1013 ment filename,
\e[4mless
\e[24m uses the original file, as normal. The input pre-
1014 processor is not called when viewing standard input. To set up an
1015 input preprocessor, set the LESSOPEN environment variable to a command
1016 line which will invoke your input preprocessor. This command line
1017 should include one occurrence of the string "%s", which will be
1018 replaced by the filename when the input preprocessor command is
1021 When
\e[4mless
\e[24m closes a file opened in such a way, it will call another pro-
1022 gram, called the input postprocessor, which may perform any desired
1023 clean-up action (such as deleting the replacement file created by
1024 LESSOPEN). This program receives two command line arguments, the orig-
1025 inal filename as entered by the user, and the name of the replacement
1026 file. To set up an input postprocessor, set the LESSCLOSE environment
1027 variable to a command line which will invoke your input postprocessor.
1028 It may include two occurrences of the string "%s"; the first is
1029 replaced with the original name of the file and the second with the
1030 name of the replacement file, which was output by LESSOPEN.
1032 For example, on many Unix systems, these two scripts will allow you to
1033 keep files in compressed format, but still let
\e[4mless
\e[24m view them directly:
1039 if [ -s /tmp/less.$$ ]; then
1051 To use these scripts, put them both where they can be executed and set
1052 LESSOPEN="lessopen.sh %s", and LESSCLOSE="lessclose.sh %s %s". More
1053 complex LESSOPEN and LESSCLOSE scripts may be written to accept other
1054 types of compressed files, and so on.
1056 It is also possible to set up an input preprocessor to pipe the file
1057 data directly to
\e[4mless,
\e[24m rather than putting the data into a replacement
1058 file. This avoids the need to decompress the entire file before start-
1059 ing to view it. An input preprocessor that works this way is called an
1060 input pipe. An input pipe, instead of writing the name of a replace-
1061 ment file on its standard output, writes the entire contents of the
1062 replacement file on its standard output. If the input pipe does not
1063 write any characters on its standard output, then there is no replace-
1064 ment file and
\e[4mless
\e[24m uses the original file, as normal. To use an input
1065 pipe, make the first character in the LESSOPEN environment variable a
1066 vertical bar (|) to signify that the input preprocessor is an input
1069 For example, on many Unix systems, this script will work like the pre-
1070 vious example scripts:
1075 *.Z) uncompress -c $1 2>/dev/null
1081 To use this script, put it where it can be executed and set
1082 LESSOPEN="|lesspipe.sh %s".
1084 Note that a preprocessor cannot output an empty file, since that is
1085 interpreted as meaning there is no replacement, and the original file
1086 is used. To avoid this, if LESSOPEN starts with two vertical bars, the
1087 exit status of the script becomes meaningful. If the exit status is
1088 zero, the output is considered to be replacement text, even if it
1089 empty. If the exit status is nonzero, any output is ignored and the
1090 original file is used. For compatibility with previous versions of
1091 \e[4mless,
\e[24m if LESSOPEN starts with only one vertical bar, the exit status of
1092 the preprocessor is ignored.
1094 When an input pipe is used, a LESSCLOSE postprocessor can be used, but
1095 it is usually not necessary since there is no replacement file to clean
1096 up. In this case, the replacement file name passed to the LESSCLOSE
1097 postprocessor is "-".
1099 For compatibility with previous versions of
\e[4mless,
\e[24m the input preproces-
1100 sor or pipe is not used if
\e[4mless
\e[24m is viewing standard input. However, if
1101 the first character of LESSOPEN is a dash (-), the input preprocessor
1102 is used on standard input as well as other files. In this case, the
1103 dash is not considered to be part of the preprocessor command. If
1104 standard input is being viewed, the input preprocessor is passed a file
1105 name consisting of a single dash. Similarly, if the first two charac-
1106 ters of LESSOPEN are vertical bar and dash (|-) or two vertical bars
1107 and a dash (||-), the input pipe is used on standard input as well as
1108 other files. Again, in this case the dash is not considered to be part
1109 of the input pipe command.
1112 \e[1mNATIONAL CHARACTER SETS
\e[0m
1113 There are three types of characters in the input file:
1116 can be displayed directly to the screen.
1119 should not be displayed directly, but are expected to be found
1120 in ordinary text files (such as backspace and tab).
1123 should not be displayed directly and are not expected to be
1124 found in text files.
1126 A "character set" is simply a description of which characters are to be
1127 considered normal, control, and binary. The LESSCHARSET environment
1128 variable may be used to select a character set. Possible values for
1131 ascii BS, TAB, NL, CR, and formfeed are control characters, all chars
1132 with values between 32 and 126 are normal, and all others are
1136 Selects an ISO 8859 character set. This is the same as ASCII,
1137 except characters between 160 and 255 are treated as normal
1140 latin1 Same as iso8859.
1142 latin9 Same as iso8859.
1144 dos Selects a character set appropriate for MS-DOS.
1146 ebcdic Selects an EBCDIC character set.
1149 Selects an EBCDIC character set used by OS/390 Unix Services.
1150 This is the EBCDIC analogue of latin1. You get similar results
1151 by setting either LESSCHARSET=IBM-1047 or LC_CTYPE=en_US in your
1154 koi8-r Selects a Russian character set.
1156 next Selects a character set appropriate for NeXT computers.
1158 utf-8 Selects the UTF-8 encoding of the ISO 10646 character set.
1159 UTF-8 is special in that it supports multi-byte characters in
1160 the input file. It is the only character set that supports
1161 multi-byte characters.
1164 Selects a character set appropriate for Microsoft Windows (cp
1167 In rare cases, it may be desired to tailor
\e[4mless
\e[24m to use a character set
1168 other than the ones definable by LESSCHARSET. In this case, the envi-
1169 ronment variable LESSCHARDEF can be used to define a character set. It
1170 should be set to a string where each character in the string represents
1171 one character in the character set. The character "." is used for a
1172 normal character, "c" for control, and "b" for binary. A decimal num-
1173 ber may be used for repetition. For example, "bccc4b." would mean
1174 character 0 is binary, 1, 2 and 3 are control, 4, 5, 6 and 7 are
1175 binary, and 8 is normal. All characters after the last are taken to be
1176 the same as the last, so characters 9 through 255 would be normal.
1177 (This is an example, and does not necessarily represent any real char-
1180 This table shows the value of LESSCHARDEF which is equivalent to each
1181 of the possible values for LESSCHARSET:
1183 ascii 8bcccbcc18b95.b
1184 dos 8bcccbcc12bc5b95.b.
1185 ebcdic 5bc6bcc7bcc41b.9b7.9b5.b..8b6.10b6.b9.7b
1186 9.8b8.17b3.3b9.7b9.8b8.6b10.b.b.b.
1187 IBM-1047 4cbcbc3b9cbccbccbb4c6bcc5b3cbbc4bc4bccbc
1189 iso8859 8bcccbcc18b95.33b.
1190 koi8-r 8bcccbcc18b95.b128.
1191 latin1 8bcccbcc18b95.33b.
1192 next 8bcccbcc18b95.bb125.bb
1194 If neither LESSCHARSET nor LESSCHARDEF is set, but any of the strings
1195 "UTF-8", "UTF8", "utf-8" or "utf8" is found in the LC_ALL, LC_CTYPE or
1196 LANG environment variables, then the default character set is utf-8.
1198 If that string is not found, but your system supports the
\e[4msetlocale
\e[0m
1199 interface,
\e[4mless
\e[24m will use setlocale to determine the character set.
1200 setlocale is controlled by setting the LANG or LC_CTYPE environment
1203 Finally, if the
\e[4msetlocale
\e[24m interface is also not available, the default
1204 character set is latin1.
1206 Control and binary characters are displayed in standout (reverse
1207 video). Each such character is displayed in caret notation if possible
1208 (e.g. ^A for control-A). Caret notation is used only if inverting the
1209 0100 bit results in a normal printable character. Otherwise, the char-
1210 acter is displayed as a hex number in angle brackets. This format can
1211 be changed by setting the LESSBINFMT environment variable. LESSBINFMT
1212 may begin with a "*" and one character to select the display attribute:
1213 "*k" is blinking, "*d" is bold, "*u" is underlined, "*s" is standout,
1214 and "*n" is normal. If LESSBINFMT does not begin with a "*", normal
1215 attribute is assumed. The remainder of LESSBINFMT is a string which
1216 may include one printf-style escape sequence (a % followed by x, X, o,
1217 d, etc.). For example, if LESSBINFMT is "*u[%x]", binary characters
1218 are displayed in underlined hexadecimal surrounded by brackets. The
1219 default if no LESSBINFMT is specified is "*s<%02X>". Warning: the
1220 result of expanding the character via LESSBINFMT must be less than 31
1223 When the character set is utf-8, the LESSUTFBINFMT environment variable
1224 acts similarly to LESSBINFMT but it applies to Unicode code points that
1225 were successfully decoded but are unsuitable for display (e.g., unas-
1226 signed code points). Its default value is "<U+%04lX>". Note that
1227 LESSUTFBINFMT and LESSBINFMT share their display attribute setting
1228 ("*x") so specifying one will affect both; LESSUTFBINFMT is read after
1229 LESSBINFMT so its setting, if any, will have priority. Problematic
1230 octets in a UTF-8 file (octets of a truncated sequence, octets of a
1231 complete but non-shortest form sequence, illegal octets, and stray
1232 trailing octets) are displayed individually using LESSBINFMT so as to
1233 facilitate diagnostic of how the UTF-8 file is ill-formed.
1237 The -P option allows you to tailor the prompt to your preference. The
1238 string given to the -P option replaces the specified prompt string.
1239 Certain characters in the string are interpreted specially. The prompt
1240 mechanism is rather complicated to provide flexibility, but the ordi-
1241 nary user need not understand the details of constructing personalized
1244 A percent sign followed by a single character is expanded according to
1245 what the following character is:
1247 %b
\e[4mX
\e[24m Replaced by the byte offset into the current input file. The b
1248 is followed by a single character (shown as
\e[4mX
\e[24m above) which spec-
1249 ifies the line whose byte offset is to be used. If the charac-
1250 ter is a "t", the byte offset of the top line in the display is
1251 used, an "m" means use the middle line, a "b" means use the bot-
1252 tom line, a "B" means use the line just after the bottom line,
1253 and a "j" means use the "target" line, as specified by the -j
1256 %B Replaced by the size of the current input file.
1258 %c Replaced by the column number of the text appearing in the first
1259 column of the screen.
1261 %d
\e[4mX
\e[24m Replaced by the page number of a line in the input file. The
1262 line to be used is determined by the
\e[4mX
\e[24m, as with the %b option.
1264 %D Replaced by the number of pages in the input file, or equiva-
1265 lently, the page number of the last line in the input file.
1267 %E Replaced by the name of the editor (from the VISUAL environment
1268 variable, or the EDITOR environment variable if VISUAL is not
1269 defined). See the discussion of the LESSEDIT feature below.
1271 %f Replaced by the name of the current input file.
1273 %F Replaced by the last component of the name of the current input
1276 %i Replaced by the index of the current file in the list of input
1279 %l
\e[4mX
\e[24m Replaced by the line number of a line in the input file. The
1280 line to be used is determined by the
\e[4mX
\e[24m, as with the %b option.
1282 %L Replaced by the line number of the last line in the input file.
1284 %m Replaced by the total number of input files.
1286 %p
\e[4mX
\e[24m Replaced by the percent into the current input file, based on
1287 byte offsets. The line used is determined by the
\e[4mX
\e[24m as with the
1290 %P
\e[4mX
\e[24m Replaced by the percent into the current input file, based on
1291 line numbers. The line used is determined by the
\e[4mX
\e[24m as with the
1296 %t Causes any trailing spaces to be removed. Usually used at the
1297 end of the string, but may appear anywhere.
1299 %x Replaced by the name of the next input file in the list.
1301 If any item is unknown (for example, the file size if input is a pipe),
1302 a question mark is printed instead.
1304 The format of the prompt string can be changed depending on certain
1305 conditions. A question mark followed by a single character acts like
1306 an "IF": depending on the following character, a condition is evalu-
1307 ated. If the condition is true, any characters following the question
1308 mark and condition character, up to a period, are included in the
1309 prompt. If the condition is false, such characters are not included.
1310 A colon appearing between the question mark and the period can be used
1311 to establish an "ELSE": any characters between the colon and the period
1312 are included in the string if and only if the IF condition is false.
1313 Condition characters (which follow a question mark) may be:
1315 ?a True if any characters have been included in the prompt so far.
1317 ?b
\e[4mX
\e[24m True if the byte offset of the specified line is known.
1319 ?B True if the size of current input file is known.
1321 ?c True if the text is horizontally shifted (%c is not zero).
1323 ?d
\e[4mX
\e[24m True if the page number of the specified line is known.
1325 ?e True if at end-of-file.
1327 ?f True if there is an input filename (that is, if input is not a
1330 ?l
\e[4mX
\e[24m True if the line number of the specified line is known.
1332 ?L True if the line number of the last line in the file is known.
1334 ?m True if there is more than one input file.
1336 ?n True if this is the first prompt in a new input file.
1338 ?p
\e[4mX
\e[24m True if the percent into the current input file, based on byte
1339 offsets, of the specified line is known.
1341 ?P
\e[4mX
\e[24m True if the percent into the current input file, based on line
1342 numbers, of the specified line is known.
1346 ?x True if there is a next input file (that is, if the current
1347 input file is not the last one).
1349 Any characters other than the special ones (question mark, colon,
1350 period, percent, and backslash) become literally part of the prompt.
1351 Any of the special characters may be included in the prompt literally
1352 by preceding it with a backslash.
1356 ?f%f:Standard input.
1358 This prompt prints the filename, if known; otherwise the string "Stan-
1361 ?f%f .?ltLine %lt:?pt%pt\%:?btByte %bt:-...
1363 This prompt would print the filename, if known. The filename is fol-
1364 lowed by the line number, if known, otherwise the percent if known,
1365 otherwise the byte offset if known. Otherwise, a dash is printed.
1366 Notice how each question mark has a matching period, and how the %
1367 after the %pt is included literally by escaping it with a backslash.
1369 ?n?f%f .?m(file %i of %m) ..?e(END) ?x- Next\: %x..%t
1371 This prints the filename if this is the first prompt in a file, fol-
1372 lowed by the "file N of N" message if there is more than one input
1373 file. Then, if we are at end-of-file, the string "(END)" is printed
1374 followed by the name of the next file, if there is one. Finally, any
1375 trailing spaces are truncated. This is the default prompt. For refer-
1376 ence, here are the defaults for the other two prompts (-m and -M
1377 respectively). Each is broken into two lines here for readability
1380 ?n?f%f .?m(file %i of %m) ..?e(END) ?x- Next\: %x.:
1381 ?pB%pB\%:byte %bB?s/%s...%t
1383 ?f%f .?n?m(file %i of %m) ..?ltlines %lt-%lb?L/%L. :
1384 byte %bB?s/%s. .?e(END) ?x- Next\: %x.:?pB%pB\%..%t
1386 And here is the default message produced by the = command:
1388 ?f%f .?m(file %i of %m) .?ltlines %lt-%lb?L/%L. .
1389 byte %bB?s/%s. ?e(END) :?pB%pB\%..%t
1391 The prompt expansion features are also used for another purpose: if an
1392 environment variable LESSEDIT is defined, it is used as the command to
1393 be executed when the v command is invoked. The LESSEDIT string is
1394 expanded in the same way as the prompt strings. The default value for
1399 Note that this expands to the editor name, followed by a + and the line
1400 number, followed by the file name. If your editor does not accept the
1401 "+linenumber" syntax, or has other differences in invocation syntax,
1402 the LESSEDIT variable can be changed to modify this default.
1406 When the environment variable LESSSECURE is set to 1,
\e[4mless
\e[24m runs in a
1407 "secure" mode. This means these features are disabled:
1413 :e the examine command.
1415 v the editing command
1419 -k use of lesskey files
1421 -t use of tags files
1423 metacharacters in filenames, such as *
1425 filename completion (TAB, ^L)
1427 Less can also be compiled to be permanently in "secure" mode.
1430 \e[1mCOMPATIBILITY WITH MORE
\e[0m
1431 If the environment variable LESS_IS_MORE is set to 1, or if the program
1432 is invoked via a file link named "more",
\e[4mless
\e[24m behaves (mostly) in con-
1433 formance with the POSIX "more" command specification. In this mode,
1434 less behaves differently in these ways:
1436 The -e option works differently. If the -e option is not set,
\e[4mless
\e[0m
1437 behaves as if the -E option were set. If the -e option is set,
\e[4mless
\e[0m
1438 behaves as if the -e and -F options were set.
1440 The -m option works differently. If the -m option is not set, the
1441 medium prompt is used, and it is prefixed with the string "--More--".
1442 If the -m option is set, the short prompt is used.
1444 The -n option acts like the -z option. The normal behavior of the -n
1445 option is unavailable in this mode.
1447 The parameter to the -p option is taken to be a
\e[4mless
\e[24m command rather
1448 than a search pattern.
1450 The LESS environment variable is ignored, and the MORE environment
1451 variable is used in its place.
1454 \e[1mENVIRONMENT VARIABLES
\e[0m
1455 Environment variables may be specified either in the system environment
1456 as usual, or in a
\e[4mlesskey
\e[24m (1) file. If environment variables are
1457 defined in more than one place, variables defined in a local lesskey
1458 file take precedence over variables defined in the system environment,
1459 which take precedence over variables defined in the system-wide lesskey
1463 Sets the number of columns on the screen. Takes precedence over
1464 the number of columns specified by the TERM variable. (But if
1465 you have a windowing system which supports TIOCGWINSZ or
1466 WIOCGETD, the window system's idea of the screen size takes
1467 precedence over the LINES and COLUMNS environment variables.)
1469 EDITOR The name of the editor (used for the v command).
1471 HOME Name of the user's home directory (used to find a lesskey file
1472 on Unix and OS/2 systems).
1475 Concatenation of the HOMEDRIVE and HOMEPATH environment vari-
1476 ables is the name of the user's home directory if the HOME vari-
1477 able is not set (only in the Windows version).
1479 INIT Name of the user's init directory (used to find a lesskey file
1482 LANG Language for determining the character set.
1485 Language for determining the character set.
1487 LESS Options which are passed to
\e[4mless
\e[24m automatically.
1490 Characters which may end an ANSI color escape sequence (default
1494 Characters which may appear between the ESC character and the
1495 end character in an ANSI color escape sequence (default
1496 "0123456789;[?!"'#%()*+ ".
1499 Format for displaying non-printable, non-control characters.
1502 Defines a character set.
1505 Selects a predefined character set.
1508 Command line to invoke the (optional) input-postprocessor.
1511 Name of the lessecho program (default "lessecho"). The lessecho
1512 program is needed to expand metacharacters, such as * and ?, in
1513 filenames on Unix systems.
1516 Editor prototype string (used for the v command). See discus-
1520 Name of the command used by the -t option to find global tags.
1521 Normally should be set to "global" if your system has the
\e[4mglobal
\e[0m
1522 (1) command. If not set, global tags are not used.
1525 Name of the history file used to remember search commands and
1526 shell commands between invocations of
\e[4mless.
\e[24m If set to "-" or
1527 "/dev/null", a history file is not used. The default is
1528 "$HOME/.lesshst" on Unix systems, "$HOME/_lesshst" on DOS and
1529 Windows systems, or "$HOME/lesshst.ini" or "$INIT/lesshst.ini"
1533 The maximum number of commands to save in the history file. The
1537 Name of the default lesskey(1) file.
1540 Name of the default system-wide lesskey(1) file.
1543 List of characters which are considered "metacharacters" by the
1547 Prefix which less will add before each metacharacter in a com-
1548 mand sent to the shell. If LESSMETAESCAPE is an empty string,
1549 commands containing metacharacters will not be passed to the
1553 Command line to invoke the (optional) input-preprocessor.
1556 Runs less in "secure" mode. See discussion under SECURITY.
1559 String to be appended to a directory name in filename comple-
1563 Format for displaying non-printable Unicode code points.
1566 Emulate the
\e[4mmore
\e[24m (1) command.
1568 LINES Sets the number of lines on the screen. Takes precedence over
1569 the number of lines specified by the TERM variable. (But if you
1570 have a windowing system which supports TIOCGWINSZ or WIOCGETD,
1571 the window system's idea of the screen size takes precedence
1572 over the LINES and COLUMNS environment variables.)
1574 MORE Options which are passed to
\e[4mless
\e[24m automatically when running in
1575 \e[4mmore
\e[24m compatible mode.
1577 PATH User's search path (used to find a lesskey file on MS-DOS and
1580 SHELL The shell used to execute the ! command, as well as to expand
1583 TERM The type of terminal on which
\e[4mless
\e[24m is being run.
1585 VISUAL The name of the editor (used for the v command).
1593 Copyright (C) 1984-2012 Mark Nudelman
1595 less is part of the GNU project and is free software. You can redis-
1596 tribute it and/or modify it under the terms of either (1) the GNU Gen-
1597 eral Public License as published by the Free Software Foundation; or
1598 (2) the Less License. See the file README in the less distribution for
1599 more details regarding redistribution. You should have received a copy
1600 of the GNU General Public License along with the source for less; see
1601 the file COPYING. If not, write to the Free Software Foundation, 59
1602 Temple Place, Suite 330, Boston, MA 02111-1307, USA. You should also
1603 have received a copy of the Less License; see the file LICENSE.
1605 less is distributed in the hope that it will be useful, but WITHOUT ANY
1606 WARRANTY; without even the implied warranty of MERCHANTABILITY or FIT-
1607 NESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
1613 Send bug reports or comments to <bug-less@gnu.org>
1614 See http://www.greenwoodsoftware.com/less/bugs.html for the latest list
1615 of known bugs in less.
1616 For more information, see the less homepage at
1617 http://www.greenwoodsoftware.com/less.
1621 Version 458: 04 Apr 2013 LESS(1)