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
11 bug-less@gnu.org or markn@greenwoodsoftware.com.
13 ======================================================================
16 Major changes between "less" versions 406 and 408
18 * Support CSI escape sequences, like SGR escape sequences.
20 * Fix bug which caused screen to fail to repaint when window is resized.
22 * Fix bug in using -i and -I flags with non-ASCII text.
24 * Fix configure bug on systems which don't support langinfo.h.
26 ======================================================================
28 Major changes between "less" versions 394 and 406
30 * Allow decimal point in number for % (percent) command.
32 * Allow decimal point in number for -j option (fraction of screen height).
34 * Make n command fetch previous pattern from history file on first search.
36 * Don't rewrite history file if it has not changed.
38 * Don't move to bottom of screen on first page.
40 * Don't output extraneous newlines, so copy & pasting lines from the
43 * The -c option has been made identical with the -C option.
45 * Allow "/dev/null" as synomym for "-" in LESSHISTFILE to indicate
46 that no history file should be used.
48 * Search can now find text which follows a null byte, if the PCRE
49 library is used, or if no-regex searching (ctrl-R) is used.
51 * Better compatibility with POSIX more specification.
53 * Make -f work for directories.
55 * Make "t" cmd traverse tags in the correct order.
57 * Allow a few binary characters in the input file before warning
58 that the file is binary.
60 * Don't warn that file is binary if it merely contains ANSI color sequences
63 * Update Unicode character tables.
65 * Support DESTDIR in Makefile.
67 * Fix bug when filename contains certain shell metacharacters such as "$".
69 * Fix bug when resizing the window while waiting for input from a pipe.
73 ======================================================================
75 Major changes between "less" versions 382 and 394
77 * Add history file to save search and shell command history between
80 * Improve behavior of history list for search and shell commands.
82 * Add -K (or --quit-on-intr) option to make less exit immediately on ctrl-C.
84 * Improve handling of UTF-8 files and commands, including better
85 line wrapping and handling double-width chars.
87 * Added LESSUTFBINFMT environment variable to control display of
88 non-printable characters in a UTF-8 file.
90 * Add --with-secure option to configure, to make it easier to
91 build a secure version of less.
93 * Show search matches in the status column even if search highlights
94 are disabled via the -G option or the ESC-u command.
96 * Improve performance when the file contains very long lines.
98 * Add "windows" charset.
100 * Add man page for lessecho.
102 * Add support for erase2 character, treated same as erase.
104 * Use ASCII lowercase/uppercase logic when operating on the command line.
106 * Update makefile for Borland C++ 5.5.1.
108 * Fix bug in calculating number of pages for %D prompt.
110 * Fix bug in handling tag file error.
112 * Fix obscure bug if input file is deleted while viewing help.
114 * Fix bug handling filenames which include square brackets.
116 * Fix possible buffer overflow in "global" tag search.
118 * Fix possible buffer overflow in usage of LESSOPEN and LESSCLOSE.
120 * Fix buffer overflow in reverse search.
122 ======================================================================
124 Major changes between "less" versions 381 and 382
126 * Removed some old copyrighted code.
127 This probably breaks OS/9 support.
129 ======================================================================
131 Major changes between "less" versions 378 and 381
133 * New -L option to disable LESSOPEN processing.
135 * Further support for large (64 bit) file addressing.
136 Large file support is now set up by the configure script.
139 Replace configure.in, acconfig.h, defines.h.top with configure.ac.
141 * Overstriking underscore with underscore is now bold or underlined
142 depending on context.
144 * Use only 7 spaces for line numbers in -N mode, if possible.
146 * Fix some bugs in handling overstriking in UTF-8 files.
148 * Fix some nroff issues in the man page.
150 ======================================================================
152 Major changes between "less" versions 376 and 378
155 Default buffer space is now 64K as documented.
156 Search highlighting works properly when used with -R.
157 Windows version works properly when input file contains carriage returns.
158 Clean up some compiler warnings.
160 ======================================================================
162 Major changes between "less" versions 358 and 376
164 * -x option can now specify multiple variable-width tab stops.
166 * -X option no longer disables keypad initialization.
167 New option --no-keypad disables keypad initialization.
169 * New commands t and T step through multiple tag matches.
170 Added support for "global(1)" tags
171 (see http://www.gnu.org/software/global/global.html).
173 * New prompt style set by option -Pw defines the message printed
174 while waiting for data in the F command.
176 * System-wide lesskey file now defaults to sysless in etc directory
177 instead of .sysless in bin directory.
178 Use "configure --sysconfdir=..." to change it.
179 (For backwards compatibility, .sysless in bin is still recognized.)
181 * Pressing RightArrow or LeftArrow while entering a number now shifts
182 the display N columns rather than editing the number itself.
184 * Status column (enabled with -J) now shows search results.
186 * Windows version sets window title.
188 * Default LESSCHARSET for MS-DOS versions is now "dos".
190 * Searching works better with ANSI (SGR) escape sequences.
191 ANSI color escape sequences are now supported in the MS-DOS (DJGPP) version.
193 * Improved performance in reading very large pipes.
195 * Eliminated some dependencies on file offets being 32 bits.
197 * Fixed problems when viewing files with very long lines.
199 * Fixed overstriking in UTF-8 mode, and overstriking tabs.
201 * Improved horizontal shifting of text using -R option with ANSI color.
203 * Improved handling of filenames containing shell metacharacters.
205 * Some fixes for EBCDIC systems.
207 * Some fixes for OS/2 systems.
209 ======================================================================
211 Major changes between "less" versions 354 and 358
213 * Add -J (--status-column) option to display a status column.
215 * Add -# (--shift) option to set default horizontal shift distance.
216 Default horizontal shift distance is now one-half screen width.
218 * Horizontal shifting does not shift line numbers if -N is in effect.
220 * Horizontal shifting acts as though -S were set, to avoid confusion.
222 ======================================================================
225 Major changes between "less" versions 352 and 354
227 * Allow space after numeric-valued command line options.
229 * Fix problem with configuring terminal libraries on some systems.
231 * Add support for PCRE regular expression library.
233 * Add --with-regex option to configure to allow manually selecting
234 a regular expression library.
236 * Fix bug compiling with SECURE = 1.
238 ======================================================================
241 Major changes between "less" versions 346 and 352
243 * Enable UTF-8 if "UTF-8" appears in locale-related environment variables.
245 * Add --with-editor option to configure script.
247 * The -M prompt and = message now show the top and bottom line number.
249 * Fix bug in running the editor on a file whose name contains quotes, etc.
251 * Fix bug in horizontal scrolling of long lines.
253 * Fix bug in doing :d on a file which contains marks.
255 * Fix bug causing cleared lines to sometimes be filled with standout,
256 bold, underline, etc. on certain terminals.
258 * Fixes for MS-DOS (DJGPP) version.
260 ======================================================================
263 Major changes between "less" versions 340 and 346
265 * The UTF-8 character set is now supported.
267 * The default character set is now latin1 rather than ascii.
269 * New option -R (--RAW-CONTROL-CHARS) is like -r but handles
270 long (wrapped) lines correctly, as long as the input contains only
271 normal text and ANSI color escape sequences.
273 * New option -F (--quit-if-one-screen) quits if the text fits on
276 * The -w option now highlights the target line of a g or p command.
278 * A system-wide lesskey file is supported (LESSKEY_SYSTEM).
280 * New escape for prompt strings: %c is replaced by column number.
282 * New escape for prompt strings: %P is replaced by percentage into
283 file, based on line number rather than byte offset.
285 * HOME and END keys now jump to beginning of file or end of file.
287 ======================================================================
290 Major changes between "less" versions 337 and 340
292 * Command line options for less may now be given in either the old
293 single-letter form, or a new long name form (--option-name).
294 See the less man page or "less --help" for the list of long option names.
296 * Command line options for lesskey may now be given in a new long name
297 form. See the lesskey man page for the list of long option names.
299 * New command -- toggles an option using the long option name.
301 * New command __ queries an option using the long option name.
303 * The old -- command is renamed as -!.
305 * If a ^P is entered between the dash and the option letter of the -
306 command, the message describing the new setting is suppressed.
308 * Lesskey files may now contain \k escape sequences to represent the
309 "special" keys (arrows, PAGE-UP/PAGE-DOWN, HOME, END, INSERT, DELETE).
311 * New command :d removes the current file from the list of files.
313 * New option -~ (like -w before version 335)
314 suppresses tildes after end-of-file.
316 * Less is now released under the GNU General Public License.
318 ======================================================================
321 Major changes between "less" versions 335 and 337
323 * Fixed bugs in "make install".
325 ======================================================================
328 Major changes between "less" versions 332 and 335
330 * The old -w flag (suppress tildes after end-of-file) has been removed.
332 * New -w flag highlights the first new line after a forward-screen.
334 * New -W flag highlights the first new line after any forward movement.
336 * Window resize works even if LINES and/or COLUMNS environment
337 variables are incorrect.
339 * New percent escapes for prompt strings:
340 %d is replaced by the page number, and
341 %D is replaced by the number of pages in the file.
343 * Added charsets "iso8859" and "ebcdic".
345 * In Windows version, uses HOMEDRIVE and HOMEPATH if HOME is not defined.
347 * Fixed some bugs causing incorrect display on DOS/Windows.
349 ======================================================================
352 Major changes between "less" versions 330 and 332
354 * Filenames from the command line are entered into the command history,
355 so UPARROW/DOWNARROW can be used to retrieve them from the :e command.
357 * Now works correctly on Windows when using a scrolling terminal
358 window (buffer larger than display window).
360 * On Windows, now restores the console screen on exit.
361 Use -X to get the old behavior.
363 * Fixed bug on Windows when CAPS-LOCK or NUM-LOCK is pressed.
365 * Fixed bug on Windows when piping output of an interactive program.
367 * Fixed bug in tags file processing when tags file has DOS-style
368 line terminators (CR/LF).
370 * Fixed compilation problem on OS/2.
372 ======================================================================
375 Major changes between "less" versions 321 and 330
377 * Now supports filenames containing spaces (in double quotes).
378 New option -" can be used to change the quoting characters.
380 * In filename completion, a slash is appended to a directory name.
381 If the environment variable LESSSEPARATOR is set, the value of
382 that variable, rather than a slash, is appended.
384 * LeftArrow and RightArrow are same as ESC-[ and ESC-].
386 * Added commands ESC-( and ESC-), same as ESC-[ and ESC-].
388 * A "quit" command defined in a lesskey file may now have an "extra"
389 string, which is used to return an exit code from less when it quits.
391 * New environment variables LESSMETACHARS and LESSMETAESCAPE provide
392 more control over how less interfaces to the shell.
394 * Ported to Microsoft Visual C compiler for Windows.
396 * Ported to DJGPP compiler for MS-DOS.
400 ======================================================================
403 Major changes between "less" versions 291 and 321
405 * Command line at bottom of screen now scrolls, so it can be longer
406 than the screen width.
408 * New commands ESC-] and ESC-[ scroll the display horizontally.
410 * New command ESC-SPACE scrolls forward a full screen, even if it
413 * Alternate modifiers for search commands: ^N is same as !,
414 ^F is same as @, and ^E is same as *.
416 * New modifier for search commands: ^K means highlight the matches
417 currently on-screen, but don't move to the first match.
419 * New modifier for search commands: ^R means don't use regular
420 expressions in the search.
422 * Environment variable LESSKEY gives name of default lesskey file.
424 * Environment variable LESSSECURE will force less to run in
427 * Command line argument "--" signals that the rest of the arguments
428 are files (not option flags).
430 * Help file (less.hlp) is no longer installed. Help text is now
431 embedded in the less executable itself.
433 * Added -Ph to change the prompt for the help text.
434 Added -Ps to change the default short prompt (same as plain -P).
436 * Ported to the Borland C compiler for MS-DOS.
438 * Ported to Windows 95 & Windows NT.
442 * Ported to GNU Hurd.
444 ======================================================================
447 Major changes between "less" versions 290 and 291
449 * Less environment variables can be specified in lesskey files.
451 * Fixed MS-DOS build.
453 ======================================================================
456 Major changes between "less" versions 278 and 290
458 * Accepts GNU-style options "--help" and "--version".
460 * OS/2 version looks for less.ini in $HOME before $INIT and $PATH.
464 ======================================================================
467 Major changes between "less" versions 252 and 278
469 * A LESSOPEN preprocessor may now pipe the converted file data to less,
470 rather than writing it to a temporary file.
472 * Search pattern highlighting has been fixed. It now highlights
473 reliably, even if a string is split across two screen lines,
476 * The -F flag (which suppress search highlighting) has been changed
477 to -G. A new flag, -g, changes search highlighting to highlight
478 only the string found by the last search command, instead of all
479 strings which match the last search command.
481 * New flag -I acts like -i, but ignores case even if the search
482 pattern contains uppercase letters.
484 * Less now checks for the environment variable VISUAL before EDITOR.
488 ======================================================================
491 Major changes between "less" versions 237 and 252
493 * Changes in line-editing keys:
494 The literal key is now ^V or ^A rather than \ (backslash).
495 Filename completion commands (TAB and ^L) are disabled
496 when typing a search pattern.
498 * Line-editing command keys can be redefined using lesskey.
500 * Lesskey with no input file defaults to $HOME/.lesskey
501 rather than standard input.
503 * New option -V displays version number of less.
505 * New option -V displays version number of lesskey.
507 * Help file less.hlp is now installed by default in /usr/local/share
508 rather than /usr/local/lib.
511 ======================================================================
514 Major changes between "less" versions 170 and 237
516 * By popular demand, text which matches the current search pattern
517 is highlighted. New -F flag disables this feature.
519 * Henry Spencer's regexp.c is now included, for systems which do not
520 have a regular expression library.
521 regexp.c is Copyright (c) 1986 by University of Toronto.
523 * New line-editing keys, including command history (arrow keys) and
524 filename completion (TAB).
526 * Input preprocessor allows modification of input files (e.g. uncompress)
527 via LESSOPEN/LESSCLOSE environment variables.
529 * New -X flag disables sending termcap "ti" and "te" (initialize and
530 deinitialize) strings to the terminal.
532 * Changing -i from within less now correctly affects a subsequent
535 * Searching for underlined or overstruck text now works when the -u
536 flag is in effect, rather than the -i flag.
538 * Use setlocale (LANG and LC_CTYPE environment variables) to determine
539 the character set if LESSCHARSET/LESSCHARDEF are not set.
541 * The default format for displaying binary characters is now standout
542 (reverse video) rather than blinking. This can still be changed by
543 setting the LESSBINFMT environment variable.
545 * Use autoconf installation technology.
549 ********************************
550 Things that may surprise you
551 ********************************
553 * When you enter text at the bottom of the screen (search string,
554 filename, etc.), some keys act different than previously.
555 Specifically, \ (backslash), ESC, TAB, BACKTAB, and control-L
556 now have line editing functions.
558 * Some previous unofficial versions of less were able to display
559 compressed files. The new LESSOPEN/LESSCLOSE feature now provides
560 this functionality in a different way.
562 * Some previous unofficial versions of less provided a -Z flag to
563 set the number of lines of text to retain between full screen scrolls.
564 The -z-n flag (that is, -z with a negative number) provides this
568 ======================================================================
571 Major changes between "less" versions 123 and 170
573 * New option -j allows target lines to be positioned anywhere on screen.
575 * New option -S truncates displayed line at the screen width,
576 rather than wrapping onto the next line.
578 * New option -y limits amount of forward scroll.
580 * New option -T specifies a "tags" file.
582 * Non-printable, non-control characters are displayed in octal.
583 Such characters, as well as control characters, are displayed
586 * New command -+ sets an option to its default.
587 * New command -- sets an option to the opposite of its default.
589 * Lesskey file may have a string appended to a key's action,
590 which acts as though typed in after the command.
592 * New commands ESC-^F and ESC-^B match arbitrary types of brackets.
594 * New command F monitors a growing file (like "tail -f").
596 * New command | pipes a section of the input file into a shell command.
598 * New command :x directly jumps to a file in the command line list.
600 * Search commands have been enhanced and reorganized:
601 n Repeat search, same direction.
602 N Repeat search, opposite direction.
603 ESC-/ Search forward thru file boundaries
604 ESC-? Search backward thru file boundaries
605 ESC-n Repeat search thru file boundaries, same direction.
606 ESC-N Repeat search thru file boundaries, opposite direction.
607 Special character * causes search to search thru file boundaries.
608 Special character @ causes search to begin at start/end of file list.
610 * Examining a new file adds it to the command line list.
611 A list of files, or an expression which matches more than one file,
612 may be examined; all of them are added to the command line list.
614 * Environment variables LESSCHARSET and LESSCHARDEF can define
615 a non-ASCII character set.
617 * Partial support for MSDOS, including options -R for repainting screen
618 on quit, -v/-V to select video mode, and -W to change window size.
621 ======================================================================
624 Major changes between "less" versions 97 and 123
626 * New option (-N) causes line numbers to be displayed in the
627 text of the file (like vi "set nu").
629 * New option (-?) prints help message immediately.
631 * New option (-r) displays "raw" control characters, without
632 mapping them to ^X notation.
634 * New option (-f) forces less to open non-regular files
637 * New option (-k) can be used to specify lesskey files by name.
639 * New option (-y) can be used to set a forward scroll limit
640 (like -h sets a backward scroll limit).
642 * File marks (set by the m command) are now preserved when a new
643 file is edited. The ' command can thus be used to switch files.
645 * New command ESC-/ searches all files (on the command line)
648 * New command ESC-n repeats previous search, spanning files.
650 * The N command has been changed to repeat the previous search
651 in the reverse direction. The old N command is still available
654 * New command ESC-N repeats previous search in the reverse
655 direction and spanning files.
657 * 8 bit characters are now supported. A new option (-g) can be
658 used to strip off the eighth bit (the previous behavior).
660 * Options which take a following string (like -t) may now
661 optionally have a space between the option letter and the string.
663 * Six new commands { } ( ) [ and ] can be used to match
664 brackets of specific types, similar to vi % command.
666 * New commands z and w move forward/backward one window and
667 simultaneously set the window size.
669 * Prompt string expansion now has %L for line number of the last
670 line in the file, and %E for the name of the editor.
671 Also, % escapes which refer to a line (b=bottom, t=top, etc.)
672 can use j for the jump target line.
674 * New environment variable LESSEDIT can be used to tailor the
675 command string passed to the editor by the v command.
677 * Examining a file which was previously examined will return
678 to the same position in the file.
680 * A "%" is expanded to the current filename and a "#" to the
681 previous filename, in both shell commands and the E command.
682 (Previously % worked only in shell commands and # worked
683 only in the E command.)
685 * New command ":ta" is equivalent to "-t".
687 * New command "s" is equivalent to "-l".
689 * The - command may be followed by "+X" to revert to the default
690 for option X, or "-X" to get the opposite of the default.
692 * Lesskey files may now include characters after the action as
693 extra input to be parsed after the action; for example:
694 "toggle-option X" to toggle a specific option X.