4 ======================================================================
6 For the latest news about less, see the "less" Web page:
7 http://www.greenwoodsoftware.com/less
8 You can also download the latest version of less from there.
10 To report bugs, suggestions or comments, send email to bug-less@gnu.org
12 ======================================================================
14 Major changes between "less" versions 530 and 551
18 * Add --wheel-lines option.
20 * Add --no-histdups option.
22 * Add --save-marks option.
24 * Support PCRE2 regular expression library.
26 * Redraw screen on SIGWINCH even if screen size doesn't change.
28 * Shell-escape filenames in history so they can be used again.
30 * Ring bell if user enters invalid long option name.
32 * Use PCRE_UTF8 flag for pcre regular expressions when in UTF-8 mode.
34 * Windows: use wide-char string to set console title.
36 * Don't count lines in initial screen if using -X with -F.
38 * Support mingw build system.
40 * Fix bug in v command on empty file.
42 * Fix bug in v command when filename contains shell metacharacters.
44 ======================================================================
46 Major changes between "less" versions 487 and 530
48 * Don't output terminal init sequence if using -F and file fits on one screen.
50 * When using -S, mark truncated lines with a special character.
51 The character can be changed or disabled via the new --rscroll option.
53 * New command M marks the last line displayed on the screen.
55 * New command ESC-m removes a line mark.
57 * Status column (enabled via -J) now shows mark letters.
59 * Status column shows search matches even if highlighting is disabled via -G.
61 * A second ESC-u command will clear search match markers in the status column.
63 * Do same ANSI escape code filtering for tag matching that we do for
64 searching, to help when viewing syntax-highlighted code.
66 * Catch SIGTERM and clean up before exiting.
68 * Fix bug initializing default charset on Windows.
70 * Handle keypad ENTER key correctly if it sends something other than newline.
72 * Fix buffering bug when using stdin with a LESSOPEN pipe.
74 * On Windows, allow 'u' in -D option to enable underlining.
76 * On Windows, use underline in sgr mode.
78 * On Windows, convert UTF-8 to multibyte if console is not UTF-8.
80 * Update Unicode tables to 2017-03-08.
82 * Pass-thru Unicode formating chars (Cf type) instead of treating them
83 as binary chars. But treat them as binary if -U is set.
85 * Fix erroneous binary file warning when UTF-8 file contains ANSI SGR sequences.
87 * Fix bugs when using LESSOPEN and switching between stdin and other files.
89 * Fix some bugs handling filenames containing shell metacharacters.
91 * Fix some memory leaks.
93 * Allow some debugging environment variables to be set in lesskey file.
96 . Use ANSI prototypes in funcs.h declarations.
97 . Fix some const mismatches.
98 . Remove archaic "register" in variable declarations.
100 ======================================================================
102 Major changes between "less" versions 481 and 487
104 * New commands ESC-{ and ESC-} to shift to start/end of displayed lines.
106 * Make search highlights work correctly when changing caselessness with -i.
108 * New option -Da in Windows version to enable SGR mode.
110 * Fix "nothing to search" error when top or bottom line on screen is empty.
112 * Fix bug when terminal has no "cm" termcap entry.
114 * Fix incorrect display when entering double-width chars in search string.
116 * Fix bug in Unicode handling that missed some double width characters.
118 * Update Unicode database to 9.0.0.
120 ======================================================================
122 Major changes between "less" versions 458 and 481
124 * Don't overwrite history file; just append to it.
126 * New command ESC-G goes to end of currently buffered data in a pipe.
128 * Disable history feature when compiled with LESSHISTFILE set to "-".
130 * In more-compatible mode, make the -p option apply to every file opened,
131 not just the first one.
133 * In more-compatible mode, change the -e option to work like -E, not -EF.
135 * Treat multiple CRs before LF are like one CR (all the CRs are hidden).
137 * Allow "extra" string in lesskey file to append to a multi-char command
138 (like a search pattern), without executing the command.
140 * Ignore -u/-U setting while viewing help file, so that
141 underline and bold chars are displayed correctly.
143 * Improve detection of "binary" files in UTF-8 mode.
145 * Fix bug with ++ commands.
147 * Fix bug where prompt was sometimes not displayed with +G.
149 * Fix possible memory corruption
151 * Fix bugs and improve performance in ampersand filtering.
153 * Automate construction of Unicode tables from Unicode database.
155 * Allow %% escape sequence in LESSOPEN variable.
157 ======================================================================
159 Major changes between "less" versions 451 and 458
161 * Allow backslash escaping of metacharacters in LESS environment variable
162 after the --use-backslash option.
164 * Don't quit if syntax errors are found in command line options.
166 * Increase sizes of some internal buffers.
168 * Fix configure bug with --with-regex=none.
170 * Fix crash with "stty rows 0".
172 * Fix Win32 attribute display bug.
174 * Fix display bug when using up/down arrow on the command line.
176 ======================================================================
178 Major changes between "less" versions 444 and 451
180 * Add ESC-F command to keep reading data until a pattern is found.
182 * Use exit code of LESSOPEN script if LESSOPEN starts with "||".
184 * When up/down arrow is used on the command line immediately after
185 typing text, the next command starting with that text is found.
187 * Add support for GNU regex.
189 * Add configure option --with-regex=none and fix compile errors
190 when compiling with no regex library.
192 * Fix bugs handling SGR sequences in Win32.
194 * Fix possible crashes caused by malformed LESSOPEN or
197 * Fix bug highlighting text which is discontiguous in the file
198 due to backspace processing.
200 * Fix bug in displaying status column when scrolling backwards
201 with -J and -S in effect.
203 ======================================================================
205 Major changes between "less" versions 443 and 444
207 * Fix bug in unget handling that can cause strange effects on the
210 * Remove vestiges of obsolete -l option that can cause a crash.
212 ======================================================================
214 Major changes between "less" versions 436 and 443
216 * Change search behavior such that when a search is given an explicit
217 pattern, the entire displayed screen is included in the search and
218 not just the portion after the target line.
220 * Add -A option to change search behavior to the old way: only
221 the portion of the screen after the target line is searched.
223 * Add %F formatting to prompt strings, replaced by the last component
226 * Control-G while editing a command exits the command.
228 * Less now exits with status 2 if control-C is pressed and -K is in effect.
230 * Fix "ungetc overflow" when passing long commands via the -p option.
232 * Fix bug in using line filtering via the & command
233 in combination with -i and -I.
235 * Fix bug in handling negative arguments to the -j option.
237 * Fix bug in handling %t in prompt strings.
239 * Improve handling of long option names.
241 * Improve percentage calculation for very large files.
243 ======================================================================
245 Major changes between "less" versions 429 and 436
247 * Don't pass "-" to non-pipe LESSOPEN unless it starts with "-".
249 * Allow a fraction as the argument to the -# (--shift) option.
251 * Fix highlight bug when underlined/overstruck text matches at end of line.
253 * Fix non-regex searches with ctrl-R.
255 ======================================================================
257 Major changes between "less" versions 424 and 429
259 * LESSOPEN pipe will now be used on standard input, if the LESSOPEN
260 environment variable begins with "|-".
262 * The -D option with one number now means use the normal background color.
264 * Don't change permissions on history file if it is not a regular file.
266 * Fix non-ANSI-compliant code that caused problems with some compilers.
268 * Fix binary file detection in UTF-8 mode.
270 * Fix display problems with long lines on "ignaw" terminals.
272 * Fix problem interrupting the line number calculation for initial prompt.
274 * Fix SGR emulation when dealing with multiple attributes (eg. bold+underline).
276 * Fix highlight bug when searching for underlined/overstruck text.
278 ======================================================================
280 Major changes between "less" versions 418 and 424
282 * New "&" command allows filtering of lines based on a pattern.
284 * Status column now displays a search match, even if the matched
285 string is scrolled off screen because -S is in effect.
287 * Improve behavior of -F option.
289 * Allow CSI character (0x9B) to work in UTF-8 mode.
291 * Output carriage return at startup in case terminal doesn't default
294 * Fix bug in '' (quote, quote) command after G command.
296 ======================================================================
298 Major changes between "less" versions 416 and 418
300 * Color escape sequences are now supported in WIN32 build.
302 * Makefile now uses EXEEXT feature of autoconf.
304 * Fix search bug when using -R and text contains ANSI color escape sequences.
306 * Fix crash when using -r with UTF-8 text containing 0x9B bytes.
308 * Fix display bug when using ' command to move less than one page forward.
310 * Update GPL to version 3.
312 ======================================================================
314 Major changes between "less" versions 409 and 416
316 * New --follow-name option makes F command follow the name of a file
317 rather than the file descriptor if an open file is renamed.
319 * Make searching with -i/-I work correctly with non-ASCII text.
323 ======================================================================
325 Major changes between "less" versions 406 and 409
327 * Support CSI escape sequences, like SGR escape sequences.
329 * Fix bug which caused screen to fail to repaint when window is resized.
331 * Fix bug in using -i and -I flags with non-ASCII text.
333 * Fix configure bug on systems which don't support langinfo.h.
335 * Fix crash when searching text containing certain invalid UTF-8 sequences.
337 ======================================================================
339 Major changes between "less" versions 394 and 406
341 * Allow decimal point in number for % (percent) command.
343 * Allow decimal point in number for -j option (fraction of screen height).
345 * Make n command fetch previous pattern from history file on first search.
347 * Don't rewrite history file if it has not changed.
349 * Don't move to bottom of screen on first page.
351 * Don't output extraneous newlines, so copy & pasting lines from the
354 * The -c option has been made identical with the -C option.
356 * Allow "/dev/null" as synomym for "-" in LESSHISTFILE to indicate
357 that no history file should be used.
359 * Search can now find text which follows a null byte, if the PCRE
360 library is used, or if no-regex searching (ctrl-R) is used.
362 * Better compatibility with POSIX more specification.
364 * Make -f work for directories.
366 * Make "t" cmd traverse tags in the correct order.
368 * Allow a few binary characters in the input file before warning
369 that the file is binary.
371 * Don't warn that file is binary if it merely contains ANSI color sequences
374 * Update Unicode character tables.
376 * Support DESTDIR in Makefile.
378 * Fix bug when filename contains certain shell metacharacters such as "$".
380 * Fix bug when resizing the window while waiting for input from a pipe.
382 * Fix configure bugs.
384 ======================================================================
386 Major changes between "less" versions 382 and 394
388 * Add history file to save search and shell command history between
391 * Improve behavior of history list for search and shell commands.
393 * Add -K (or --quit-on-intr) option to make less exit immediately on ctrl-C.
395 * Improve handling of UTF-8 files and commands, including better
396 line wrapping and handling double-width chars.
398 * Added LESSUTFBINFMT environment variable to control display of
399 non-printable characters in a UTF-8 file.
401 * Add --with-secure option to configure, to make it easier to
402 build a secure version of less.
404 * Show search matches in the status column even if search highlights
405 are disabled via the -G option or the ESC-u command.
407 * Improve performance when the file contains very long lines.
409 * Add "windows" charset.
411 * Add man page for lessecho.
413 * Add support for erase2 character, treated same as erase.
415 * Use ASCII lowercase/uppercase logic when operating on the command line.
417 * Update makefile for Borland C++ 5.5.1.
419 * Fix bug in calculating number of pages for %D prompt.
421 * Fix bug in handling tag file error.
423 * Fix obscure bug if input file is deleted while viewing help.
425 * Fix bug handling filenames which include square brackets.
427 * Fix possible buffer overflow in "global" tag search.
429 * Fix possible buffer overflow in usage of LESSOPEN and LESSCLOSE.
431 * Fix buffer overflow in reverse search.
433 ======================================================================
435 Major changes between "less" versions 381 and 382
437 * Removed some old copyrighted code.
438 This probably breaks OS/9 support.
440 ======================================================================
442 Major changes between "less" versions 378 and 381
444 * New -L option to disable LESSOPEN processing.
446 * Further support for large (64 bit) file addressing.
447 Large file support is now set up by the configure script.
450 Replace configure.in, acconfig.h, defines.h.top with configure.ac.
452 * Overstriking underscore with underscore is now bold or underlined
453 depending on context.
455 * Use only 7 spaces for line numbers in -N mode, if possible.
457 * Fix some bugs in handling overstriking in UTF-8 files.
459 * Fix some nroff issues in the man page.
461 ======================================================================
463 Major changes between "less" versions 376 and 378
466 Default buffer space is now 64K as documented.
467 Search highlighting works properly when used with -R.
468 Windows version works properly when input file contains carriage returns.
469 Clean up some compiler warnings.
471 ======================================================================
473 Major changes between "less" versions 358 and 376
475 * -x option can now specify multiple variable-width tab stops.
477 * -X option no longer disables keypad initialization.
478 New option --no-keypad disables keypad initialization.
480 * New commands t and T step through multiple tag matches.
481 Added support for "global(1)" tags
482 (see http://www.gnu.org/software/global/global.html).
484 * New prompt style set by option -Pw defines the message printed
485 while waiting for data in the F command.
487 * System-wide lesskey file now defaults to sysless in etc directory
488 instead of .sysless in bin directory.
489 Use "configure --sysconfdir=..." to change it.
490 (For backwards compatibility, .sysless in bin is still recognized.)
492 * Pressing RightArrow or LeftArrow while entering a number now shifts
493 the display N columns rather than editing the number itself.
495 * Status column (enabled with -J) now shows search results.
497 * Windows version sets window title.
499 * Default LESSCHARSET for MS-DOS versions is now "dos".
501 * Searching works better with ANSI (SGR) escape sequences.
502 ANSI color escape sequences are now supported in the MS-DOS (DJGPP) version.
504 * Improved performance in reading very large pipes.
506 * Eliminated some dependencies on file offets being 32 bits.
508 * Fixed problems when viewing files with very long lines.
510 * Fixed overstriking in UTF-8 mode, and overstriking tabs.
512 * Improved horizontal shifting of text using -R option with ANSI color.
514 * Improved handling of filenames containing shell metacharacters.
516 * Some fixes for EBCDIC systems.
518 * Some fixes for OS/2 systems.
520 ======================================================================
522 Major changes between "less" versions 354 and 358
524 * Add -J (--status-column) option to display a status column.
526 * Add -# (--shift) option to set default horizontal shift distance.
527 Default horizontal shift distance is now one-half screen width.
529 * Horizontal shifting does not shift line numbers if -N is in effect.
531 * Horizontal shifting acts as though -S were set, to avoid confusion.
533 ======================================================================
536 Major changes between "less" versions 352 and 354
538 * Allow space after numeric-valued command line options.
540 * Fix problem with configuring terminal libraries on some systems.
542 * Add support for PCRE regular expression library.
544 * Add --with-regex option to configure to allow manually selecting
545 a regular expression library.
547 * Fix bug compiling with SECURE = 1.
549 ======================================================================
552 Major changes between "less" versions 346 and 352
554 * Enable UTF-8 if "UTF-8" appears in locale-related environment variables.
556 * Add --with-editor option to configure script.
558 * The -M prompt and = message now show the top and bottom line number.
560 * Fix bug in running the editor on a file whose name contains quotes, etc.
562 * Fix bug in horizontal scrolling of long lines.
564 * Fix bug in doing :d on a file which contains marks.
566 * Fix bug causing cleared lines to sometimes be filled with standout,
567 bold, underline, etc. on certain terminals.
569 * Fixes for MS-DOS (DJGPP) version.
571 ======================================================================
574 Major changes between "less" versions 340 and 346
576 * The UTF-8 character set is now supported.
578 * The default character set is now latin1 rather than ascii.
580 * New option -R (--RAW-CONTROL-CHARS) is like -r but handles
581 long (wrapped) lines correctly, as long as the input contains only
582 normal text and ANSI color escape sequences.
584 * New option -F (--quit-if-one-screen) quits if the text fits on
587 * The -w option now highlights the target line of a g or p command.
589 * A system-wide lesskey file is supported (LESSKEY_SYSTEM).
591 * New escape for prompt strings: %c is replaced by column number.
593 * New escape for prompt strings: %P is replaced by percentage into
594 file, based on line number rather than byte offset.
596 * HOME and END keys now jump to beginning of file or end of file.
598 ======================================================================
601 Major changes between "less" versions 337 and 340
603 * Command line options for less may now be given in either the old
604 single-letter form, or a new long name form (--option-name).
605 See the less man page or "less --help" for the list of long option names.
607 * Command line options for lesskey may now be given in a new long name
608 form. See the lesskey man page for the list of long option names.
610 * New command -- toggles an option using the long option name.
612 * New command __ queries an option using the long option name.
614 * The old -- command is renamed as -!.
616 * If a ^P is entered between the dash and the option letter of the -
617 command, the message describing the new setting is suppressed.
619 * Lesskey files may now contain \k escape sequences to represent the
620 "special" keys (arrows, PAGE-UP/PAGE-DOWN, HOME, END, INSERT, DELETE).
622 * New command :d removes the current file from the list of files.
624 * New option -~ (like -w before version 335)
625 suppresses tildes after end-of-file.
627 * Less is now released under the GNU General Public License.
629 ======================================================================
632 Major changes between "less" versions 335 and 337
634 * Fixed bugs in "make install".
636 ======================================================================
639 Major changes between "less" versions 332 and 335
641 * The old -w flag (suppress tildes after end-of-file) has been removed.
643 * New -w flag highlights the first new line after a forward-screen.
645 * New -W flag highlights the first new line after any forward movement.
647 * Window resize works even if LINES and/or COLUMNS environment
648 variables are incorrect.
650 * New percent escapes for prompt strings:
651 %d is replaced by the page number, and
652 %D is replaced by the number of pages in the file.
654 * Added charsets "iso8859" and "ebcdic".
656 * In Windows version, uses HOMEDRIVE and HOMEPATH if HOME is not defined.
658 * Fixed some bugs causing incorrect display on DOS/Windows.
660 ======================================================================
663 Major changes between "less" versions 330 and 332
665 * Filenames from the command line are entered into the command history,
666 so UPARROW/DOWNARROW can be used to retrieve them from the :e command.
668 * Now works correctly on Windows when using a scrolling terminal
669 window (buffer larger than display window).
671 * On Windows, now restores the console screen on exit.
672 Use -X to get the old behavior.
674 * Fixed bug on Windows when CAPS-LOCK or NUM-LOCK is pressed.
676 * Fixed bug on Windows when piping output of an interactive program.
678 * Fixed bug in tags file processing when tags file has DOS-style
679 line terminators (CR/LF).
681 * Fixed compilation problem on OS/2.
683 ======================================================================
686 Major changes between "less" versions 321 and 330
688 * Now supports filenames containing spaces (in double quotes).
689 New option -" can be used to change the quoting characters.
691 * In filename completion, a slash is appended to a directory name.
692 If the environment variable LESSSEPARATOR is set, the value of
693 that variable, rather than a slash, is appended.
695 * LeftArrow and RightArrow are same as ESC-[ and ESC-].
697 * Added commands ESC-( and ESC-), same as ESC-[ and ESC-].
699 * A "quit" command defined in a lesskey file may now have an "extra"
700 string, which is used to return an exit code from less when it quits.
702 * New environment variables LESSMETACHARS and LESSMETAESCAPE provide
703 more control over how less interfaces to the shell.
705 * Ported to Microsoft Visual C compiler for Windows.
707 * Ported to DJGPP compiler for MS-DOS.
711 ======================================================================
714 Major changes between "less" versions 291 and 321
716 * Command line at bottom of screen now scrolls, so it can be longer
717 than the screen width.
719 * New commands ESC-] and ESC-[ scroll the display horizontally.
721 * New command ESC-SPACE scrolls forward a full screen, even if it
724 * Alternate modifiers for search commands: ^N is same as !,
725 ^F is same as @, and ^E is same as *.
727 * New modifier for search commands: ^K means highlight the matches
728 currently on-screen, but don't move to the first match.
730 * New modifier for search commands: ^R means don't use regular
731 expressions in the search.
733 * Environment variable LESSKEY gives name of default lesskey file.
735 * Environment variable LESSSECURE will force less to run in
738 * Command line argument "--" signals that the rest of the arguments
739 are files (not option flags).
741 * Help file (less.hlp) is no longer installed. Help text is now
742 embedded in the less executable itself.
744 * Added -Ph to change the prompt for the help text.
745 Added -Ps to change the default short prompt (same as plain -P).
747 * Ported to the Borland C compiler for MS-DOS.
749 * Ported to Windows 95 & Windows NT.
753 * Ported to GNU Hurd.
755 ======================================================================
758 Major changes between "less" versions 290 and 291
760 * Less environment variables can be specified in lesskey files.
762 * Fixed MS-DOS build.
764 ======================================================================
767 Major changes between "less" versions 278 and 290
769 * Accepts GNU-style options "--help" and "--version".
771 * OS/2 version looks for less.ini in $HOME before $INIT and $PATH.
775 ======================================================================
778 Major changes between "less" versions 252 and 278
780 * A LESSOPEN preprocessor may now pipe the converted file data to less,
781 rather than writing it to a temporary file.
783 * Search pattern highlighting has been fixed. It now highlights
784 reliably, even if a string is split across two screen lines,
787 * The -F flag (which suppress search highlighting) has been changed
788 to -G. A new flag, -g, changes search highlighting to highlight
789 only the string found by the last search command, instead of all
790 strings which match the last search command.
792 * New flag -I acts like -i, but ignores case even if the search
793 pattern contains uppercase letters.
795 * Less now checks for the environment variable VISUAL before EDITOR.
799 ======================================================================
802 Major changes between "less" versions 237 and 252
804 * Changes in line-editing keys:
805 The literal key is now ^V or ^A rather than \ (backslash).
806 Filename completion commands (TAB and ^L) are disabled
807 when typing a search pattern.
809 * Line-editing command keys can be redefined using lesskey.
811 * Lesskey with no input file defaults to $HOME/.lesskey
812 rather than standard input.
814 * New option -V displays version number of less.
816 * New option -V displays version number of lesskey.
818 * Help file less.hlp is now installed by default in /usr/local/share
819 rather than /usr/local/lib.
822 ======================================================================
825 Major changes between "less" versions 170 and 237
827 * By popular demand, text which matches the current search pattern
828 is highlighted. New -F flag disables this feature.
830 * Henry Spencer's regexp.c is now included, for systems which do not
831 have a regular expression library.
832 regexp.c is Copyright (c) 1986 by University of Toronto.
834 * New line-editing keys, including command history (arrow keys) and
835 filename completion (TAB).
837 * Input preprocessor allows modification of input files (e.g. uncompress)
838 via LESSOPEN/LESSCLOSE environment variables.
840 * New -X flag disables sending termcap "ti" and "te" (initialize and
841 deinitialize) strings to the terminal.
843 * Changing -i from within less now correctly affects a subsequent
846 * Searching for underlined or overstruck text now works when the -u
847 flag is in effect, rather than the -i flag.
849 * Use setlocale (LANG and LC_CTYPE environment variables) to determine
850 the character set if LESSCHARSET/LESSCHARDEF are not set.
852 * The default format for displaying binary characters is now standout
853 (reverse video) rather than blinking. This can still be changed by
854 setting the LESSBINFMT environment variable.
856 * Use autoconf installation technology.
860 ********************************
861 Things that may surprise you
862 ********************************
864 * When you enter text at the bottom of the screen (search string,
865 filename, etc.), some keys act different than previously.
866 Specifically, \ (backslash), ESC, TAB, BACKTAB, and control-L
867 now have line editing functions.
869 * Some previous unofficial versions of less were able to display
870 compressed files. The new LESSOPEN/LESSCLOSE feature now provides
871 this functionality in a different way.
873 * Some previous unofficial versions of less provided a -Z flag to
874 set the number of lines of text to retain between full screen scrolls.
875 The -z-n flag (that is, -z with a negative number) provides this
879 ======================================================================
882 Major changes between "less" versions 123 and 170
884 * New option -j allows target lines to be positioned anywhere on screen.
886 * New option -S truncates displayed line at the screen width,
887 rather than wrapping onto the next line.
889 * New option -y limits amount of forward scroll.
891 * New option -T specifies a "tags" file.
893 * Non-printable, non-control characters are displayed in octal.
894 Such characters, as well as control characters, are displayed
897 * New command -+ sets an option to its default.
898 * New command -- sets an option to the opposite of its default.
900 * Lesskey file may have a string appended to a key's action,
901 which acts as though typed in after the command.
903 * New commands ESC-^F and ESC-^B match arbitrary types of brackets.
905 * New command F monitors a growing file (like "tail -f").
907 * New command | pipes a section of the input file into a shell command.
909 * New command :x directly jumps to a file in the command line list.
911 * Search commands have been enhanced and reorganized:
912 n Repeat search, same direction.
913 N Repeat search, opposite direction.
914 ESC-/ Search forward thru file boundaries
915 ESC-? Search backward thru file boundaries
916 ESC-n Repeat search thru file boundaries, same direction.
917 ESC-N Repeat search thru file boundaries, opposite direction.
918 Special character * causes search to search thru file boundaries.
919 Special character @ causes search to begin at start/end of file list.
921 * Examining a new file adds it to the command line list.
922 A list of files, or an expression which matches more than one file,
923 may be examined; all of them are added to the command line list.
925 * Environment variables LESSCHARSET and LESSCHARDEF can define
926 a non-ASCII character set.
928 * Partial support for MSDOS, including options -R for repainting screen
929 on quit, -v/-V to select video mode, and -W to change window size.
932 ======================================================================
935 Major changes between "less" versions 97 and 123
937 * New option (-N) causes line numbers to be displayed in the
938 text of the file (like vi "set nu").
940 * New option (-?) prints help message immediately.
942 * New option (-r) displays "raw" control characters, without
943 mapping them to ^X notation.
945 * New option (-f) forces less to open non-regular files
948 * New option (-k) can be used to specify lesskey files by name.
950 * New option (-y) can be used to set a forward scroll limit
951 (like -h sets a backward scroll limit).
953 * File marks (set by the m command) are now preserved when a new
954 file is edited. The ' command can thus be used to switch files.
956 * New command ESC-/ searches all files (on the command line)
959 * New command ESC-n repeats previous search, spanning files.
961 * The N command has been changed to repeat the previous search
962 in the reverse direction. The old N command is still available
965 * New command ESC-N repeats previous search in the reverse
966 direction and spanning files.
968 * 8 bit characters are now supported. A new option (-g) can be
969 used to strip off the eighth bit (the previous behavior).
971 * Options which take a following string (like -t) may now
972 optionally have a space between the option letter and the string.
974 * Six new commands { } ( ) [ and ] can be used to match
975 brackets of specific types, similar to vi % command.
977 * New commands z and w move forward/backward one window and
978 simultaneously set the window size.
980 * Prompt string expansion now has %L for line number of the last
981 line in the file, and %E for the name of the editor.
982 Also, % escapes which refer to a line (b=bottom, t=top, etc.)
983 can use j for the jump target line.
985 * New environment variable LESSEDIT can be used to tailor the
986 command string passed to the editor by the v command.
988 * Examining a file which was previously examined will return
989 to the same position in the file.
991 * A "%" is expanded to the current filename and a "#" to the
992 previous filename, in both shell commands and the E command.
993 (Previously % worked only in shell commands and # worked
994 only in the E command.)
996 * New command ":ta" is equivalent to "-t".
998 * New command "s" is equivalent to "-l".
1000 * The - command may be followed by "+X" to revert to the default
1001 for option X, or "-X" to get the opposite of the default.
1003 * Lesskey files may now include characters after the action as
1004 extra input to be parsed after the action; for example:
1005 "toggle-option X" to toggle a specific option X.