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version.c
1019 lines (1015 loc) · 52.8 KB
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version.c
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/*
* Copyright (C) 1984-2024 Mark Nudelman
*
* You may distribute under the terms of either the GNU General Public
* License or the Less License, as specified in the README file.
*
* For more information, see the README file.
*/
/*
----------------------- CHANGE HISTORY --------------------------
1/29/84 Allowed use on standard input
2/1/84 Added E, N, P commands
4/17/84 Added '=' command, 'stop' signal handling
4/20/84 Added line folding
v2 4/27/84 Fixed '=' command to use BOTTOM_PLUS_ONE,
instead of TOP, added 'p' & 'v' commands
v3 5/3/84 Added -m and -t options, '-' command
v4 5/3/84 Added LESS environment variable
v5 5/3/84 New comments, fixed '-' command slightly
v6 5/15/84 Added -Q, visual bell
v7 5/24/84 Fixed jump_back(n) bug: n should count real
lines, not folded lines. Also allow number on G command.
v8 5/30/84 Re-do -q and -Q commands
v9 9/25/84 Added "+<cmd>" argument
v10 10/10/84 Fixed bug in -b<n> argument processing
v11 10/18/84 Made error() ring bell if \n not entered.
-----------------------------------------------------------------
v12 2/13/85 Reorganized signal handling and made portable to 4.2bsd.
v13 2/16/85 Reword error message for '-' command.
v14 2/22/85 Added -bf and -bp variants of -b.
v15 2/25/85 Miscellaneous changes.
v16 3/13/85 Added -u flag for backspace processing.
v17 4/13/85 Added j and k commands, changed -t default.
v18 4/20/85 Rewrote signal handling code.
v19 5/2/85 Got rid of "verbose" eq_message().
Made search() scroll in some cases.
v20 5/21/85 Fixed screen.c ioctls for System V.
v21 5/23/85 Fixed some first_cmd bugs.
v22 5/24/85 Added support for no RECOMP nor REGCMP.
v23 5/25/85 Miscellaneous changes and prettying up.
Posted to USENET.
-----------------------------------------------------------------
v24 6/3/85 Added ti,te terminal init & de-init.
(Thanks to Mike Kersenbrock)
v25 6/8/85 Added -U flag, standout mode underlining.
v26 6/9/85 Added -M flag.
Use underline termcap (us) if it exists.
v27 6/15/85 Renamed some variables to make unique in
6 chars. Minor fix to -m.
v28 6/28/85 Fixed right margin bug.
v29 6/28/85 Incorporated M.Rose's changes to signal.c
v30 6/29/85 Fixed stupid bug in argument processing.
v31 7/15/85 Added -p flag, changed repaint algorithm.
Added kludge for magic cookie terminals.
v32 7/16/85 Added cat_file if output not a tty.
v33 7/23/85 Added -e flag and EDITOR.
v34 7/26/85 Added -s flag.
v35 7/27/85 Rewrote option handling; added option.c.
v36 7/29/85 Fixed -e flag to work if not last file.
v37 8/10/85 Added -x flag.
v38 8/19/85 Changed prompting; created prompt.c.
v39 8/24/85 (Not -p) does not initially clear screen.
v40 8/26/85 Added "skipping" indicator in forw().
Posted to USENET.
-----------------------------------------------------------------
v41 9/17/85 ONLY_RETURN, control char commands,
faster search, other minor fixes.
v42 9/25/85 Added ++ command line syntax;
ch_fsize for pipes.
v43 10/15/85 Added -h flag, changed prim.c algorithms.
v44 10/16/85 Made END print in all cases of eof;
ignore SIGTTOU after receiv ing SIGTSTP.
v45 10/16/85 Never print backspaces unless -u.
v46 10/24/85 Backwards scroll in jump_loc.
v47 10/30/85 Fixed bug in edit(): *first_cmd==0
v48 11/16/85 Use TIOCSETN instead of TIOCSETP.
Added marks (m and ' commands).
Posted to USENET.
-----------------------------------------------------------------
v49 1/9/86 Fixed bug: signal didn't clear mcc.
v50 1/15/86 Added ' (quote) to gomark.
v51 1/16/86 Added + cmd, fixed problem if first_cmd
fails, made g cmd sort of "work" on pipes
ev en if bof is no longer buffered.
v52 1/17/86 Made short files work better.
v53 1/20/86 Added -P option.
v54 1/20/86 Changed help to use HELPFILE.
v55 1/23/86 Messages work better if not tty output.
v56 1/24/86 Added -l option.
v57 1/31/86 Fixed -l to get confirmation before
ov erwriting an existing file.
v58 8/28/86 Added filename globbing.
v59 9/15/86 Fixed some bugs with very long filenames.
v60 9/26/86 Incorporated changes from Leith (Casey)
Leedom for boldface and -z option.
v61 9/26/86 Got rid of annoying repaints after ! cmd.
Posted to USENET.
-----------------------------------------------------------------
v62 12/23/86 Added is_directory(); change -z default to
-1 instead of 24; cat-and-exit if -e and
file is less than a screenful.
v63 1/8/87 Fixed bug in cat-and-exit if > 1 file.
v64 1/12/87 Changed puts/putstr, putc/putchr,
getc/getchr to av oid name conflict with
stdio functions.
v65 1/26/87 Allowed '-' command to change NUMBER
v alued options (thanks to Gary Puckering)
v66 2/13/87 Fixed bug: prepaint should use force=1.
v67 2/24/87 Added !! and % expansion to ! command.
v68 2/25/87 Added SIGWINCH and TIOCGWINSZ support;
changed is_directory to bad_file.
(thanks to J. Robert Ward)
v69 2/25/87 Added SIGWIND and WIOCGETD (for Unix PC).
v70 3/13/87 Changed help cmd from 'h' to 'H'; better
error msgs in bad_file, errno_message.
v71 5/11/87 Changed -p to -c, made triple -c/-C
for clear-eol like more's -c.
v72 6/26/87 Added -E, -L, use $SHELL in lsystem().
(thanks to Stev e Spearman)
v73 6/26/87 Allow Examine "#" for previous file.
Posted to USENET 8/25/87.
-----------------------------------------------------------------
v74 9/18/87 Fix conflict in EOF symbol with stdio.h,
Make os.c more portable to BSD.
v75 9/23/87 Fix problems in get_term (thanks to
Paul Eggert); new backwards scrolling in
jump_loc (thanks to Marion Hakanson).
v76 9/23/87 Added -i flag; allow single "!" to
inv oke a shell (thanks to Franco Barber).
v77 9/24/87 Added -n flag and line number support.
v78 9/25/87 Fixed problem with prompts longer than
the screen width.
v79 9/29/87 Added the _ command.
v80 10/6/87 Allow signal to break out of linenum scan.
v81 10/6/87 Allow -b to be changed from within less.
v82 10/7/87 Add cmd_decode to use a table for key
binding (thanks to Dav id Nason).
v83 10/9/87 Allow .less file for user-defined keys.
v84 10/11/87 Fix -e/-E problems (thanks to Felix Lee).
v85 10/15/87 Search now keeps track of line numbers.
v86 10/20/87 Added -B option and autobuf; fixed
"pipe error" bug.
v87 3/1/88 Fix bug re BSD signals while reading file.
v88 3/12/88 Use new format for -P option (thanks to
der Mouse), allow "+-c" without message,
fix bug re BSD hangup.
v89 3/18/88 Turn off line numbers if linenum scan
is interrupted.
v90 3/30/88 Allow -P from within less.
v91 3/30/88 Added tags file support (new -t option)
(thanks to Brian Campbell).
v92 4/4/88 Added -+option syntax.
v93 4/11/88 Add support for slow input (thanks to
Joe Orost & apologies for taking almost
3 years to get this in!)
v94 4/11/88 Redo reading/signal stuff.
v95 4/20/88 Repaint screen better after signal.
v96 4/21/88 Add /! and ?! commands.
v97 5/17/88 Allow -l/-L from within less.
Eliminate some static arrays (use calloc).
Posted to USENET.
-----------------------------------------------------------------
v98 10/14/88 Fix incorrect calloc call; uninitialized
var in exec_mca; core dump on unknown TERM.
Make v cmd work if past last line of file.
Fix some signal bugs.
v99 10/29/88 Allow space between -X and string,
when X is a string-valued option.
v100 1/5/89 Fix globbing bug when $SHELL not set;
allow spaces after -t command.
v101 1/6/89 Fix problem with long (truncated) lines
in tags file (thanks to Neil Dixon).
v102 1/6/89 Fix bug with E# when no prev file;
allow spaces after -l command.
v103 3/14/89 Add -N, -f and -? options. Add z and w
commands. Add %L for prompt strings.
v104 3/16/89 Added EDITPROTO.
v105 3/20/89 Fix bug in find_linenum which cached
incorrectly on long lines.
v106 3/31/89 Added -k option and multiple lesskey
files.
v107 4/27/89 Add 8-bit char support and -g option.
Split option code into 3 files.
v108 5/5/89 Allocate position table dynamically
(thanks to Paul Eggert); change % command
from "percent" to vi-style brace finder.
v109 5/10/89 Added ESC-% command, split prim.c.
v110 5/24/89 Fixed bug in + option; fixed repaint bug
under Sun windows (thanks to Paul Eggert).
v111 5/25/89 Generalized # and % expansion; use
calloc for some error messages.
v112 5/30/89 Get rid of ESC-%, add {}()[] commands.
v113 5/31/89 Optimize lseeks (thanks to Paul Eggert).
v114 7/25/89 Added ESC-/ and ESC-/! commands.
v115 7/26/89 Added ESC-n command.
v116 7/31/89 Added find_pos to optimize g command.
v117 8/1/89 Change -f option to -r.
v118 8/2/89 Save positions for all previous files,
not just the immediately previous one.
v119 8/7/89 Save marks across file boundaries.
Add file handle stuff.
v120 8/11/89 Add :ta command.
v121 8/16/89 Add -f option.
v122 8/30/89 Fix performance with many buffers.
v123 8/31/89 Verbose prompts for string options.
Posted beta to USENET.
-----------------------------------------------------------------
v124 9/18/89 Reorganize search commands,
N = rev, ESC-n = span, add ESC-N.
v125 9/18/89 Fix tab bug (thanks to Alex Liu).
Fix EOF bug when both -w and -c.
v126 10/25/89 Add -j option.
v127 10/27/89 Fix problems with blank lines before BOF.
v128 10/27/89 Add %bj, etc. to prompt strings.
v129 11/3/89 Add -+,-- commands; add set-option and
unset-option to lesskey.
v130 11/6/89 Generalize A_EXTRA to string, remove
set-option, unset-option from lesskey.
v131 11/7/89 Changed name of EDITPROTO to LESSEDIT.
v132 11/8/89 Allow editing of command prefix.
v133 11/16/89 Add -y option (thanks to Jeff Sullivan).
v134 12/1/89 Glob filenames in the -l command.
v135 12/5/89 Combined {}()[] commands into one, and
added ESC-^F and ESC-^B commands.
v136 1/20/90 Added -S, -R flags. Added | command.
Added warning for binary files. (thanks
to Richard Brittain and J. Sullivan).
v137 1/21/90 Rewrote horrible pappend code.
Added * notation for hi-bit chars.
v138 1/24/90 Fix magic cookie terminal handling.
Get rid of "cleanup" loop in ch_get.
v139 1/27/90 Added MSDOS support. (many thanks
to Richard Brittain).
v140 2/7/90 Editing a new file adds it to the
command line list.
v141 2/8/90 Add edit_list for editing >1 file.
v142 2/10/90 Add :x command.
v143 2/11/90 Add * and @ modifies to search cmds.
Change ESC-/ cmd from /@* to / *.
v144 3/1/90 Messed around with ch_zero;
no real change.
v145 3/2/90 Added -R and -v/-V for MSDOS;
renamed FILENAME to avoid conflict.
v146 3/5/90 Pull cmdbuf functions out of command.c
v147 3/7/90 Implement ?@; fix multi-file edit bugs.
v148 3/29/90 Fixed bug in :e<file> then :e#.
v149 4/3/90 Change error,ierror,query to use PARG.
v150 4/6/90 Add LESS_CHARSET, LESS_CHARDEF.
v151 4/13/90 Remove -g option; clean up ispipe.
v152 4/14/90 lsystem() closes input file, for
editors which require exclusive open.
v153 4/18/90 Fix bug if SHELL unset;
fix bug in overstrike control char.
v154 4/25/90 Output to fd 2 via buffer.
v155 4/30/90 Ignore -i if uppercase in pattern
(thanks to Michael Rendell.)
v156 5/3/90 Remove scroll limits in forw() & back();
causes problems with -c.
v157 5/4/90 Forward search starts at next real line
(not screen line) after jump target.
v158 6/14/90 Added F command.
v159 7/29/90 Fix bug in exiting: output not flushed.
v160 7/29/90 Clear screen before initial output w/ -c.
v161 7/29/90 Add -T flag.
v162 8/14/90 Fix bug with +F on command line.
v163 8/21/90 Added LESSBINFMT variable.
v164 9/5/90 Added -p, LINES, COLUMNS and
unset mark ' == BOF, for 1003.2 D5.
v165 9/6/90 At EOF with -c set, don't display empty
screen when try to page forward.
v166 9/6/90 Fix G when final line in file wraps.
v167 9/11/90 Translate CR/LF -> LF for 1003.2.
v168 9/13/90 Return to curr file if "tag not found".
v169 12/12/90 G goes to EOF even if file has grown.
v170 1/17/91 Add optimization for BSD _setjmp;
fix #include ioctl.h TERMIO problem.
(thanks to Paul Eggert)
Posted to USENET.
-----------------------------------------------------------------
v171 3/6/91 Fix -? bug in get_filename.
v172 3/15/91 Fix G bug in empty file.
Fix bug with ?\n and -i and uppercase
pattern at EOF!
(thanks to Paul Eggert)
v173 3/17/91 Change N cmd to not permanently change
direction. (thanks to Brian Matthews)
v174 3/18/91 Fix bug with namelogfile not getting
cleared when change files.
v175 3/18/91 Fix bug with ++cmd on command line.
(thanks to Jim Meyering)
v176 4/2/91 Change | to not force current screen,
include marked line, start/end from
top of screen. Improve search speed.
(thanks to Don Mears)
v177 4/2/91 Add LESSHELP variable.
Fix bug with F command with -e.
Try /dev/tty for input before using fd 2.
Patches posted to USENET 4/2/91.
-----------------------------------------------------------------
v178 4/8/91 Fixed bug in globbing logfile name.
(thanks to Jim Meyering)
v179 4/9/91 Allow negative -z for screen-relative.
v180 4/9/91 Clear to eos rather than eol if "db";
don't use "sr" if "da".
(thanks to Tor Lillqvist)
v181 4/18/91 Fixed bug with "negative" chars 80 - FF.
(thanks to Benny Sander Hofmann)
v182 5/16/91 Fixed bug with attribute at EOL.
(thanks to Brian Matthews)
v183 6/1/91 Rewrite linstall to do smart config.
v184 7/11/91 Process \b in searches based on -u
rather than -i.
v185 7/11/91 -Pxxx sets short prompt; assume SIGWINCH
after a SIGSTOP. (thanks to Ken Laprade)
-----------------------------------------------------------------
v186 4/20/92 Port to MS-DOS (Microsoft C).
v187 4/23/92 Added -D option & TAB_COMPLETE_FILENAME.
v188 4/28/92 Added command line editing features.
v189 12/8/92 Fix mem overrun in anscreen.c:init;
fix edit_list to recover from bin file.
v190 2/13/93 Make TAB enter one filename at a time;
create ^L with old TAB functionality.
v191 3/10/93 Defer creating "flash" page for MS-DOS.
v192 9/6/93 Add BACK-TAB.
v193 9/17/93 Simplify binary_file handling.
v194 1/4/94 Add rudiments of alt_filename handling.
v195 1/11/94 Port back to Unix; support keypad.
-----------------------------------------------------------------
v196 6/7/94 Fix bug with bad filename; fix IFILE
type problem. (thanks to David MacKenzie)
v197 6/7/94 Fix bug with .less tables inserted wrong.
v198 6/23/94 Use autoconf installation technology.
(thanks to David MacKenzie)
v199 6/29/94 Fix MS-DOS build (thanks to Tim Wiegman).
v200 7/25/94 Clean up copyright, minor fixes.
Posted to prep.ai.mit.edu
-----------------------------------------------------------------
v201 7/27/94 Check for no memcpy; add casts to calloc;
look for regcmp in libgen.a.
(thanks to Kaveh Ghazi).
v202 7/28/94 Fix bug in edit_next/edit_prev with
non-existent files.
v203 8/2/94 Fix a variety of configuration bugs on
various systems. (thanks to Sakai
Kiyotaka, Harald Koenig, Bjorn Brox,
Teemu Rantanen, and Thorsten Lockert)
v204 8/3/94 Use strerror if available.
(thanks to J.T. Conklin)
v205 8/5/94 Fix bug in finding "me" termcap entry.
(thanks to Andreas Stolcke)
8/10/94 v205+: Change BUFSIZ to LBUFSIZE to avoid name
conflict with stdio.h.
Posted to prep.ai.mit.edu
-----------------------------------------------------------------
v206 8/10/94 Use initial_scrpos for -t to avoid
displaying first page before init().
(thanks to Dominique Petitpierre)
v207 8/12/94 Fix bug if stdout is not tty.
v208 8/16/94 Fix bug in close_altfile if goto err1
in edit_ifile. (Thanks to M.J. Hewitt)
v209 8/16/94 Change scroll to wscroll to avoid
conflict with library function.
v210 8/16/94 Fix bug with bold on 8 bit chars.
(thanks to Vitor Duarte)
v211 8/16/94 Don't quit on EOI in jump_loc / forw.
v212 8/18/94 Use time_t if available.
v213 8/20/94 Allow ospeed to be defined in termcap.h.
v214 8/20/94 Added HILITE_SEARCH, -F, ESC-u cmd.
(thanks to Paul Lew and Bob Byrnes)
v215 8/23/94 Fix -i toggle behavior.
v216 8/23/94 Process BS in all searches, not only -u.
v217 8/24/94 Added -X flag.
v218 8/24/94 Reimplement undo_search.
v219 8/24/94 Find tags marked with line number
instead of pattern.
v220 8/24/94 Stay at same position after SIG_WINCH.
v221 8/24/94 Fix bug in file percentage in big file.
v222 8/25/94 Do better if can't reopen current file.
v223 8/27/94 Support setlocale.
(thanks to Robert Joop)
v224 8/29/94 Revert v216: process BS in search
only if -u.
v225 9/6/94 Rewrite undo_search again: toggle.
v226 9/15/94 Configuration fixes.
(thanks to David MacKenzie)
v227 9/19/94 Fixed strerror config problem.
Posted to prep.ai.mit.edu
-----------------------------------------------------------------
v228 9/21/94 Fix bug in signals: repeated calls to
get_editkeys overflowed st_edittable.
v229 9/21/94 Fix "Nothing to search" error if -a
and SRCH_PAST_EOF.
v230 9/21/94 Don't print extra error msg in search
after regerror().
v231 9/22/94 Fix hilite bug if search matches 0 chars.
(thanks to John Polstra)
v232 9/23/94 Deal with weird systems that have
termios.h but not tcgetattr().
Posted to prep.ai.mit.edu
-----------------------------------------------------------------
v233 9/26/94 Use get_term() instead of pos_init() in
psignals to re-get lower_left termcap.
(Thanks to John Malecki)
v234 9/26/94 Make MIDDLE closer to middle of screen.
v235 9/27/94 Use local strchr if system doesn't have.
v236 9/28/94 Don't use libucb; use libterm if
libtermcap & libcurses doesn't work.
(Fix for Solaris; thanks to Frank Kaefer)
v237 9/30/94 Use system isupper() etc if provided.
Posted to prep.ai.mit.edu
-----------------------------------------------------------------
v238 10/6/94 Make binary non-blinking if LESSBINFMT
is set to a string without a *.
v239 10/7/94 Don't let delimit_word run back past
beginning of cmdbuf.
v240 10/10/94 Don't write into termcap buffer.
(Thanks to Benoit Speckel)
v241 10/13/94 New lesskey file format.
Don't expand filenames in search command.
v242 10/14/94 Allow lesskey specification of "literal".
v243 10/14/94 Add #stop command to lesskey.
v244 10/16/94 Add -f flag to lesskey.
v245 10/25/94 Allow TAB_COMPLETE_FILENAME to be undefd.
v246 10/27/94 Move help file to /usr/local/share.
v247 10/27/94 Add -V option.
v248 11/5/94 Add -V option to lesskey.
v249 11/5/94 Remove -f flag from lesskey; default
input file is ~/.lesskey.in, not stdin.
v250 11/7/94 Lesskey input file "-" means stdin.
v251 11/9/94 Convert cfgetospeed result to ospeed.
(Thanks to Andrew Chernov)
v252 11/16/94 Change default lesskey input file from
.lesskey.in to .lesskey.
Posted to prep.ai.mit.edu
-----------------------------------------------------------------
v253 11/21/94 Fix bug when tags file has a backslash.
v254 12/6/94 Fix -k option.
v255 12/8/94 Add #define EXAMINE to disable :e etc.
v256 12/10/94 Change highlighting: only highlite search
results (but now it is reliable).
v257 12/10/94 Add goto_line and repaint_highlight
to optimize highlight repaints.
v258 12/12/94 Fixup in hilite_line if BS_SPECIAL.
v259 12/12/94 Convert to autoconf 2.0.
v260 12/13/94 Add SECURE define.
v261 12/14/94 Use system WERASE char as EC_W_BACKSPACE.
v262 12/16/94 Add -g/-G flag and screen_hilite.
v263 12/20/94 Reimplement/optimize -G flag behavior.
v264 12/23/94 Allow EXTRA string after line-edit cmd
in lesskey file.
v265 12/24/94 Add LESSOPEN=|cmd syntax.
v266 12/26/94 Add -I flag.
v267 12/28/94 Formalize the four-byte header emitted
by a LESSOPEN pipe.
v268 12/28/94 Get rid of four-byte header.
v269 1/2/95 Close alt file before open new one.
Avoids multiple popen().
v270 1/3/95 Use VISUAL; use S_ISDIR/S_ISREG; fix
config problem with Solaris POSIX regcomp.
v271 1/4/95 Don't quit on read error.
v272 1/5/95 Get rid of -L.
v273 1/6/95 Fix ch_ungetchar bug; don't call
LESSOPEN on a pipe.
v274 1/6/95 Ported to OS/2 (thanks to Kai Uwe Rommel)
v275 1/18/95 Fix bug if toggle -G at EOF.
v276 1/30/95 Fix OS/2 version.
v277 1/31/95 Add "next" charset; don't display ^X
for X > 128.
v278 2/14/95 Change default for -G.
Posted to prep.ai.mit.edu
-----------------------------------------------------------------
v279 2/22/95 Add GNU options --help, --version.
Minor config fixes.
v280 2/24/95 Clean up calls to glob(); don't set #
if we can't open the new file.
v281 2/24/95 Repeat search should turn on hilites.
v282 3/2/95 Minor fixes.
v283 3/2/95 Fix homefile; make OS2 look in $HOME.
v284 3/2/95 Error if "v" on LESSOPENed file;
"%" figures out file size on pipe.
v285 3/7/95 Don't set # in lsystem;
lesskey try $HOME first.
v286 3/7/95 Reformat change history (too much free time?).
v287 3/8/95 Fix hilite bug if overstrike multiple chars.
v288 3/8/95 Allow lesskey to override get_editkey keys.
v289 3/9/95 Fix adj_hilite bug when line gets processed by
hilite_line more than once.
v290 3/9/95 Make configure automatically. Fix Sequent problem
with incompatible sigsetmask().
Posted to prep.ai.mit.edu
-----------------------------------------------------------------
v291 3/21/95 Add #env to lesskey. Fix MS-DOS build.
Posted to simtel.
-----------------------------------------------------------------
v292 4/24/95 Add MS-DOS support for Borland C.
Fix arrow keys in MS-DOS versions.
v293 4/28/95 Add auto-versioning stuff to make dist.
v294 5/12/95 Fix Borland build.
v295 1/20/96 Fix search on squished file; add /@@.
v296 1/23/96 Allow cmdbuf larger than screen width.
v297 1/24/96 Don't call termcap if tgetent fails;
add #defines for buffers.
v298 1/24/96 Change @@ to ^K.
Add alternate search modifiers ^N, ^F, ^E.
v299 1/25/96 Fix percent overflow in jump_percent (thanks to Brent Wiese);
don't send "ti" after shell command till RETURN pressed.
v300 1/25/96 Change -U to print tabs as ^I.
v301 1/30/96 Make hilites work in cmd F output.
v302 1/31/96 Fix cmd F to notice window-change signals.
v303 1/31/96 Add ESC-SPACE command.
v304 2/1/96 Add ^R search modifier; add LESSSECURE.
v305 2/2/96 Workaround Linux /proc kernel bug; add LESSKEY.
v306 3/16/96 Minor fixes.
v307 3/25/96 Allow cmd line arg "--"; fix DOS & OS/2 defines.h.
v308 4/4/96 Port to OS-9 (thanks to Boisy Pitre); fix -d.
v309 4/9/96 Fix OS-9 version; fix tags bug with "$".
v310 4/10/96 Get rid of HELPFILE.
v311 4/22/96 Add Windows32 support; merge doscreen.c into screen.c.
v312 4/24/96 Don't quit after "cannot reopen" error.
v313 4/25/96 Added horizontal scrolling.
v314 4/26/96 Modified -e to quit on reaching end of a squished file.
v315 4/26/96 Fix "!;TAB" bug.
v316 5/2/96 Make "|a" when (a < curr screen) go to end of curr screen.
v317 5/14/96 Various fixes for the MS-DOS and OS/2 builds.
Added ## and %% handling for filenames
v318 5/29/96 Port to OS-9 Microware compiler; minor fixes
(thanks to Martin Gregorie).
v319 7/8/96 Fix Windows port (thanks to Jeff Paquette).
v320 7/11/96 Final fixes for Windows port.
v321 7/18/96 Minor fixes.
Posted to Web page.
-----------------------------------------------------------------
v322 8/13/96 Fix bug in shell escape from help file; add support for
Microsoft Visual C under Windows; numerous small fixes.
v323 8/19/96 Fixes for Windows version (thanks to Simon Munton);
fix for Linux library weirdness (thanks to Jim Diamond);
port to DJGPP (thanks to Eli Zaretskii).
v324 8/21/96 Add support for spaces in filenames (thanks to Simon Munton).
v325 8/21/96 Add lessecho, for spaces in filenames under Unix.
v326 8/27/96 Fix DJGPP version.
v327 9/1/96 Reorganize lglob, make spaces in filenames work better in Unix.
v328 10/7/96 Append / to directory name in filename completion.
Fix MS-DOS and OS-9 versions.
v329 10/11/96 Fix more MS-DOS bugs; add LESSSEPARATOR; add -" option.
Add LESSMETACHARS, LESSMETAESCAPE.
v330 10/21/96 Minor fixes.
Posted to Web page.
-----------------------------------------------------------------
v331 4/22/97 Various Windows fixes (thanks to Gurusamy Sarathy).
v332 4/22/97 Enter filenames from cmd line into edit history.
Posted to Web page.
-----------------------------------------------------------------
v333 3/4/99 Changed -w to highlite new line after forward movement.
v334 3/9/99 Avoid overflowing prompt buffer; add %d and %D.
v335 3/20/99 Add EBCDIC support (thanks to Thomas Dorner).
Use HOMEDRIVE/HOMEPATH on Windows (thanks to Preston Bannister).
Posted to Web page.
-----------------------------------------------------------------
v336 4/8/99 Fix installation bugs.
v337 4/9/99 Fix another installation bug.
Posted to Web page.
-----------------------------------------------------------------
v338 4/13/99 Add support for long option names.
v339 4/18/99 Add \k, long option names to lesskey. Add -^P. Add :d.
v340 4/21/99 Add regexec2. Fix Windows build.
Posted to Web page.
-----------------------------------------------------------------
v341 5/6/99 Add -F option; %c & ?c prompt escapes.
(Thanks to Michele Maltoni)
v342 7/22/99 Add system-wide lesskey file; allow GPL or Less License.
v343 9/23/99 Support UTF-8 (Thanks to Robert Brady).
Add %P and ?P in prompts.
v344 10/27/99 -w highlights target line of g and p commands.
v345 10/29/99 Make -R pass thru ESC but not other control chars.
Posted to Web page.
-----------------------------------------------------------------
v346 11/4/99 Fix bugs in long option processing; R cmd should clear hilites.
Posted to Web page.
-----------------------------------------------------------------
v347 12/13/99 Fixes for DJGPP version (thanks to Eli Zaretskii).
v348 12/28/99 Fix deleting file with marks (thanks to Dimitar Jekov).
Fix color problem in DJGPP version (thanks to Eli Zaretskii).
v349 1/24/00 Fix minor DJGPP bugs; check environment vars for UTF-8;
add --with-editor (thanks to Eli, Markus Kuhn, Thomas Schoepf).
v350 3/1/00 Fix clear-while-standout bug.
v351 3/5/00 Change -M and = prompts to show top & bottom line number.
Posted to Web page.
-----------------------------------------------------------------
v352 3/8/00 Fix scan_option NULL dereference.
-----------------------------------------------------------------
v353 3/20/00 Fix SECURE compile bug, allow space after numeric option.
v354 3/23/00 Add support for PCRE; add --with-regex configure option.
-----------------------------------------------------------------
v355 6/28/00 Add -# option (thanks to Andy Levinson).
v356 7/5/00 Add -J option.
v357 7/6/00 Support sigprocmask.
-----------------------------------------------------------------
v358 7/8/00 Fix problems with #stop in lesskey file.
Posted to Web page.
-----------------------------------------------------------------
v359 9/10/00 Fixes for Win32 display problems (thanks to Maurizio Vairani).
v360 1/17/01 Move sysless to etc.
v361 12/4/01 Add IBM-1047 charset & EBCDIC fixes (thanks to Thomas Dorner).
Fix 32 bit dependencies (thanks to Paul Eggert).
Fix UTF-8 overstriking (thanks to Robert Brady).
v362 12/4/01 Make status column show search targets.
v363 12/6/01 Add --no-keypad option.
Add variable width tabstops (thanks to Peter Samuelson).
v364 12/10/01 Better handling of very long lines in input;
Fix horizontal shifting of colored text.
v365 12/11/01 Fix overstriking of tabs;
Add support for global(1) and multiple tag matches
(thanks to Shigio Yamaguchi and Tim Vanderhoek).
v366 12/11/01 Fixes for OS/2 (thanks to Kyosuke Tokoro).
v367 12/13/01 Allow -D and -x options to terminate without dollar sign;
Right/left arrow when entering N are shift cmds, not line edit.
v368 12/18/01 Update lesskey commands.
v370 12/23/01 Fix tags error messages.
Posted to Web page.
-----------------------------------------------------------------
v371 12/26/01 Fix new_file bug; use popen in Windows version;
fix some compiler warnings.
v372 12/29/01 Make -b be in units of 1K.
v373 1/14/02 Improve handling of filenames containing shell metachars.
v374 2/7/02 Fix memory leak; fix bug in -x argument parsing.
v375 4/7/02 Fix searching for SGR sequences; fix SECURE build;
add SGR support to DJGPP version (thanks to Eli Zaretskii).
v376 6/10/02 Fix bug in overstriking multibyte UTF-8 characters
(thanks to Jungshik Shin).
Posted to Web page.
-----------------------------------------------------------------
v377 9/10/02 Fix bug in Windows version when file contains CR;
fix bug in search highlights with -R;
make initial buffer limit really be 64K not unlimited.
v378 9/30/02 Misc bug fixes and compiler warning cleanup.
Posted to Web page.
-----------------------------------------------------------------
v379 11/23/02 Add -L option; fix bug with ctrl-K in lesskey files;
improve UTF-8 overstriking and underscore overstriking;
fix minor man page problems; change to autoconf 2.54.
v380 11/24/02 Make LINENUM same as POSITION.
v381 11/28/02 Make -N use 7 columns for line number if possible.
-----------------------------------------------------------------
v382 2/3/04 Remove copyrighted code.
-----------------------------------------------------------------
v383 2/16/04 Add history file; add -K option; improve UTF-8 handling;
fix some signed char bugs (thanks to Christian Biere);
fix some upper/lower case bugs (thanks to Bjoern Jacke);
add erase2 char (thanks to David Lawrence);
add windows charset (thanks to Dimitar Zhekov).
v384 2/20/04 Improvements in UTF-8 handling.
v385 2/23/04 Fix UTF-8 output bug.
-----------------------------------------------------------------
v386 9/13/05 Improvements to UTF-8 shift & color (thanks to Charles Levert);
protect against invalid LESSOPEN and LESSCLOSE values.
v387 9/14/05 Update Charles Levert's UTF-8 patch.
v388 9/14/05 Change history behavior; change most sprintf calls to snprintf.
v389 9/14/05 Fix copy & paste with long lines; improve performance of
expand_linebuf; fix crash in init_mlist;
v390 9/15/05 Show search matches in status column even if -G is set.
-----------------------------------------------------------------
v391 9/17/05 Fix bugs.
v392 10/14/05 Fix line wrapping bug.
v393 10/19/05 Allow multiple attributes per char; fix bold+underline bug
(thanks again to Charles Levert).
v394 11/8/05 Fix prompt bug; fix compile problem in Windows build.
-----------------------------------------------------------------
v395 1/12/07 Update Unicode tables (thanks to Charles Levert);
don't chmod if LESSHISTFILE = /dev/null;
make -f work for directories; support DESTDIR in Makefile;
fix sigset_t detection in configure;
make "t" cmd traverse tags in correct order
v396 1/13/07 Add compatibility with POSIX more.
v397 3/21/07 Allow decimal point in number for % command;
Allow decimal point in number for -j option;
Allow n command to fetch last search pattern from history
(thanks to arno).
v398 3/22/07 Don't rewrite history file if not necessary;
fix bug when filenames contain "$".
v399 3/22/07 Don't move to bottom of screen at startup;
don't output extraneous newlines.
v400 3/23/07 Allow search to find pattern after null byte (PCRE and no-regex)
(thanks to Michael Constant).
-----------------------------------------------------------------
v401 3/24/07 Minor documentation fixes.
v402 3/30/07 Fix autoconf bug when memcpy etc are inline;
fix bug in terminating number following -j option.
v403 5/25/07 Fix Windows build.
v404 6/5/07 Fix display bug with F command and long lines.
v405 6/17/07 Fix display bug when using -w option.
v406 6/17/07 Fix secure build.
v407 8/16/07 Fix bugs; support CSI chars.
v408 10/1/07 Fix bug in -i with non-ASCII chars.
v409 10/12/07 Fix crash when viewing text with invalid UTF-8 sequences.
v411 11/6/07 Fix case-insensitive searching with non-ASCII text.
v412 11/6/07 Use symbolic SEEK constants.
v413 11/6/07 Fix search highlight bug with non-ASCII text.
v414 11/6/07 Fix display bug with no-wrap terminals.
v415 11/14/07 Add --follow-name option.
v416 11/22/07 Fix crash when searching text with invalid UTF-8 sequences.
v417 12/31/07 Don't support single-char CSI in UTF-8 mode;
fix bug with -R and invalid CSI sequences;
fix bug searching text with SGR sequences with -r;
emulate SGR sequences in WIN32 build.
v418 12/31/07 Clean up.
-----------------------------------------------------------------
v419 1/16/08 Make CSI char 0x9B work in UTF-8 mode (thanks to Colin Watson).
v420 2/24/08 Add & command; fix -F option; fix '' after G.
v421 2/24/08 Ignore filtered lines when searching.
v422 3/2/08 Output CR at startup.
v423 5/27/08 Clean up.
v424 6/16/08 Fix compile bug with pcre; don't filter help file.
v425 7/14/08 Fix non-ANSI code in list handling in ch.c.
v426 10/27/08 Fix ignaw terminal handling (thanks to Per Hedeland);
fix binary file detection in UTF-8 mode.
v427 3/16/09 A few Win32 fixes (thanks to Jason Hood).
v428 3/30/09 Add "|-" syntax to LESSOPEN.
v429 4/10/09 Fix search highlighting bug with underlined text.
-----------------------------------------------------------------
v430 4/22/09 Don't pass "-" to non-pipe LESSOPEN unless it starts with "-".
v431 4/29/09 Fix highlight bug when match is at end of line.
v432 6/27/09 Better fix for highlight bugs;
fix new problems with ignaw terminals.
v433 6/28/09 Cleanup search code.
v434 6/29/09 More cleanup.
v435 7/04/09 Fix bugs with non-regex filtering.
v436 7/05/09 Fix memory leak.
-----------------------------------------------------------------
v437 7/14/09 Fix bug in handling some long option names;
make percentage calculation more accurate.
v438 12/29/10 Fix bugs with -i/-I and & filtering;
exit with status 2 on ctrl-C with -K.
v439 12/31/10 Add -A option.
v440 1/5/11 Fix bug displaying prompt after = command.
v441 1/21/11 Fix semi-infinite loop if no newlines in file;
make new -A behavior the default.
-----------------------------------------------------------------
v442 3/2/11 Fix search bug.
Add ctrl-G line edit command.
v443 4/9/11 Fix Windows build.
v444 6/8/11 Fix ungetc bug; remove vestiges of obsolete -l option.
-----------------------------------------------------------------
v445 10/19/11 Fix hilite bug in backwards scroll with -J.
Fix hilite bug with backspaces.
Fix bugs handling SGR sequences in Win32 (thanks to Eric Lee).
Add support for GNU regex (thanks to Reuben Thomas).
v446 5/15/12 Up/down arrows in cmd editing search for matching cmd.
v447 5/21/12 Add ESC-F command, two-pipe LESSOPEN syntax.
v448 6/15/12 Print name of regex library in version message.
v449 6/23/12 Allow config option --with-regex=none.
v450 7/4/12 Fix EOF bug with ESC-F.
v451 7/20/12 Fix typo.
-----------------------------------------------------------------
v452 10/19/12 Fix --with-regex=none, fix "stty 0", fix Win32.
Don't quit if errors in cmd line options.
v453 10/27/12 Increase buffer sizes.
v454 11/5/12 Fix typo.
v455 11/5/12 Fix typo.
v456 11/8/12 Fix option string incompatibility.
v457 12/8/12 Use new option string syntax only after --use-backslash.
v458 4/4/13 Fix display bug in using up/down in cmd buffer.
-----------------------------------------------------------------
v459 5/6/13 Fix ++ bug.
v460 6/19/13 Automate construction of Unicode tables.
v461 6/21/13 Collapse multiple CRs before LF.
v462 11/26/13 Don't overwrite history file, just append to it.
v463 7/13/14 Misc. fixes.
v464 7/19/14 Fix bugs & improve performance in & filtering
(thanks to John Sullivan).
v465 8/9/14 More fixes from John Sullivan.
v466 8/23/14 Add colon to LESSANSIMIDCHARS.
v467 9/18/14 Misc. fixes.
v468 9/18/14 Fix typo
v469 10/2/14 Allow extra string in command to append to a multichar
cmd without executing it; fix bug using GNU regex.
v470 10/5/14 Fix some compiler warnings.
v471 12/14/14 Fix unget issues with prompt. Allow disabling history
when compiled value of LESSHISTFILE = "-".
v473 12/19/14 Fix prompt bug with stdin and -^P in lesskey extra string.
v474 1/30/15 Fix bug in backwards search with match on bottom line.
Make follow mode reopen file if file shrinks.
v475 3/2/15 Fix possible buffer overrun with invalid UTF-8;
fix bug when compiled with no regex; fix non-match search.
v476 5/3/15 Update man pages.
v477 5/19/15 Fix off-by-one in jump_forw_buffered;
don't add FAKE_* files to cmd history.
v478 5/21/15 Fix nonportable pointer usage in hilite tree.
v479 7/6/15 Allow %% escapes in LESSOPEN variable.
v480 7/24/15 Fix bug in no-regex searches; support MSVC v1900.
v481 8/20/15 Fix broken -g option.
-----------------------------------------------------------------
v482 2/25/16 Update Unicode database to "2015-06-16, 20:24:00 GMT [KW]".
v483 2/27/16 Regenerate hilite when change search caselessness.
(Thanks to Jason Hood)
Fix bug when terminal has no "cm". (Thanks to Noel Cragg)
v484 9/20/16 Update to Unicode 9.0.0 database.
v485 10/21/16 Fix "nothing to search" bug when top/bottom line is empty;
Display line numbers in bold. (thanks to Jason Hood);
Fix incorrect display when entering double-width chars in
search string.
v486 10/22/16 New commands ESC-{ and ESC-} to shift to start/end of
displayed lines; new option -Da in Windows version to
enable SGR mode (thanks to Jason Hood).
v487 10/23/16 configure --help formatting.
-----------------------------------------------------------------
v488 2/23/17 Fix memory leaks in search (thanks to John Brooks).
v489 3/30/17 Make -F not do init/deinit if file fits on one screen
(thanks to Jindrich Novy).
v490 4/5/17 Switch to ANSI prototypes in funcs.h; remove "register".
v491 4/7/17 Fix signed char bug.
v492 4/21/17 Handle SIGTERM.
v493 6/22/17 Fix bug initializing charset in MSDOS build.
v494 6/26/17 Update Unicode tables; make Cf chars composing not binary.
v495 7/3/17 Improve binary file detection (thanks to Bela Lubkin);
do -R filter when matching tags (thanks to Matthew Malcomson).
v496 7/5/17 Add LESSRSCROLL marker.
v497 7/5/17 Sync.
v498 7/7/17 Fix early truncation of text if last char is double-width.
v499 7/10/17 Misc fixes.
v500 7/11/17 Fix bug where certain env variables couldn't be set in lesskey.
v501 7/12/17 Make sure rscroll char is standout by default.
v502 7/13/17 Control rscroll char via command line option not env variable.
v503 7/13/17 Switch to git.
v504 7/13/17 Call opt_rscroll at startup; change mkhelp.c to mkhelp.pl.
v505 7/17/17 Add M and ESC-M commands;
fix buffer handling with stdin and LESSOPEN.
v506 7/17/17 On Windows, convert UTF-8 to multibyte if console is not UTF-8;
handle extended chars on input (thanks to Jason Hood).
v507 7/18/17 Fix some bugs handling filenames containing shell metachars.
v508 7/19/17 Fix bugs when using LESSOPEN to read stdin.
v509 7/19/17 Fix another stdin bug.
v510 7/20/17 Fix bug in determining when to reopen a file.
v511 7/25/17 Fix bugs in recent MSDOS changes (thanks to Jason Hood).
v512 7/26/17 Fix MSDOS build.
v513 7/26/17 Fix switch to normal attr at end of line with -R and rscroll.
v514 7/27/17 Fix bug in fcomplete when pattern does not match a file.
v515 7/28/17 Allow 'u' in -D option on Windows.
v516 7/29/17 Fix bug using LESSOPEN with filename containing metachars.
v517 7/30/17 Status column shows matches even if hiliting is disabled via -G.
v518 8/1/17 Use underline in sgr mode in MSDOS (thanks to Jason Hood).
v519 8/10/17 Fix rscroll bug when last char of line starts coloration.
v520 9/3/17 Fix compiler warning.
v521 10/20/17 Fix binary file warning in UTF-8 files with SGI sequences.
v522 10/20/17 Handle keypad ENTER key properly.
v523 10/23/17 Cleanup.
v524 10/24/17 Fix getcc bug.
v525 10/24/17 Change M command to mark last displayed line.
v526 10/25/17 Fix search hilite bug introduced in v517.
v527 10/30/17 Fix search hilite bug on last page with -a.
v528 11/3/17 Make second ESC-u clear status column.
v529 11/12/17 Display Unicode formatting chars in hex if -U is set.
v530 12/2/17 Minor doc change and add missing VOID_PARAM.
-----------------------------------------------------------------
v531 5/13/18 Fix bug with v on empty file; fix bug with v on file with
metachars in name; add --nohistdups option.
v532 7/27/18 Redraw screen on SIGWINCH even if screen size doesn't change.
v533 8/1/18 Shell escape filenames in history; use PCRE_UTF8 flag;
use wide-chars for Windows console title (thanks to Jason Hood).
v534 8/9/18 Support PCRE2.
v535 8/16/18 Don't count lines of initial screen if using -X with -F
(thanks to Linus Torvalds).
v536 8/31/18 Use descriptive error messages for PCRE2.
v537 8/31/18 Support mingw build system (thanks to Mike Soyka).
v538 9/3/18 Clean up some WIN32 code.
v539 9/13/18 Fix spurious input on Windows with CAPSLOCK.
v540 10/29/18 Add --mouse option.
v541 10/30/18 Add --MOUSE option.
v542 11/6/18 Add mouse support for WIN32; add --wheel-lines option.
(thanks to Jason Hood).
v543 11/12/18 Code cleanup.
v544 11/16/18 Don't init/deinit keyboard/mouse if quit due to -F.
v545 11/22/18 Fix Windows build, memory leaks.
v546 11/29/18 Add --save-marks option.
v547 11/30/18 Fix some bugs with saved marks.
v548 12/14/18 Ignore mouse input when line editing.
v549 2/10/19 Support X11 mouse extension 1006;
Win32 fixes (thanks to Jason Hood).
v550 2/16/19 Fix Win32 build; don't enable mouse unless --mouse is set.
v551 6/10/19 Doc changes.
-----------------------------------------------------------------
v552 7/8/19 Update Unicode tables.
v553 10/17/19 Support tinfow; handle zero-width Hangul chars.
v554 1/19/20 Remove erroneous free().
v555 3/15/20 Display error msg immediately when toggle -o without stdin.
v556 3/15/20 Update copyright.
v557 3/21/20 Fix memory corruption with libtermcap.
v558 4/17/20 Don't init terminal if -F and file fits on one screen (WIN32).
v559 4/19/20 Handle deinit correctly on WIN32.
v560 5/3/20 Fix regression when command results in no movement;
fix some less.nro issues (thanks to Bjarni I. Gislason).
v561 5/11/20 Fix erroneous EOF calculation when F command is interrupted.
v562 5/19/20 Update Unicode tables; minor doc formatting.
v563 6/13/20 Fix crash due to realpath() incompatibility.
v564 8/25/20 Handle realpath consistently; update docs.
v565 11/3/20 Add ESC-U command, optimize calls to realpath().
v566 11/25/20 Fix crash when reopening a file while using LESSOPEN;
support OSC 8 hyperlinks.
v567 11/25/20 Fix typo.
v568 11/29/20 Fix some hyperlink bugs; add ^W search modifier
(thanks to Arminius); allow Makefile.aut to use Python
instead of Perl (thanks to Charlie Lin).
v569 12/1/20 Allow multiple & filters (thanks to Mattias Johansson),
allow ^X to exit F command.
v570 12/12/20 Better handling of multiple + or -p options;
fix bugs in horizontal scrolling.
v571 12/30/20 Add --line-num-width and --status-col-width options.
v572 1/4/21 Save lastmark in history file; don't toggle mouse reporting;
implement termcap delays.
v573 1/9/21 Limit eof bell to 1 per second.
v574 1/13/21 Add incremental search.
v575 1/17/21 Fix build without HILITE_SEARCH;
fix bug with ^K in lesskey extra string.
v576 2/4/21 Make sure search result is visible; add --use-color and --color.
v577 2/9/21 Use ttyname to get name of tty device.
v578 2/9/21 Doc
v579 2/14/21 Fix double-width char bugs and non-match search crash.
v580 3/2/21 Some color fixes; fix compiler warnings; some lesstest support.
v581 4/6/21 Ignore SIGTSTP in secure mode; don't print "skipping" when filtering.
v582 4/21/21 Less now reads lesskey source file rather than binary;
fix bug in finding tags with backslashes.
v583 4/21/21 Use XDG_CONFIG_HOME and XDG_DATA_HOME to find files.
v584 4/30/21 Add --file-size option.
v585 5/2/21 Allow color desc W per man page.
v586 5/7/21 Doc changes.
v587 5/27/21 Fix --with-secure; fix --file-size message on Windows;
fix colored search hilite in colored text; don't exit
if -F and screen is resized; fix memcpy usage.
v588 5/27/21 Fix release.
v589 5/29/21 Copyright & build changes.
v590 6/3/21 Fix non-autoconf Makefiles.
v591 8/8/21 Use \kB for backspace key in lesskey; add more \k codes;
handle multibyte chars in prompt.
v592 8/24/21 Add --status-line option; limit use of /proc kludge; add --header.
v593 8/30/21 Add header columns, --no-number-headers.
v594 10/1/21 Let regex library handle caseless; add --redraw-on-quit option;
add #version to lesskey.
v595 10/12/21 Add H color type; add += to lesskey var section;
add --search-options.
v596 11/8/21 Look for lesskey in $HOME/.config.
v597 11/16/21 Fix bugs in --header.
v598 12/6/21 Look for lesshst in $XDG_STATE_HOME and $HOME/.local/state.
v599 12/28/21 Defer moving to lower left in some cases;
suppress TAB expansion in some cases.
v600 1/7/22 Use /dev/tty if cannot open ttyname().
v601 1/31/22 Add --exit-follow-on-close option.
v602 3/1/22 Doc changes.
v603 3/14/22 Fix --header.
v604 5/14/22 Fix termlib detection; fix non-ASCII input on Windows.
v605 6/14/22 Update version number.
v606 7/17/22 Fix bug with multibyte chars and --incsearch;
escape filenames in LESSCLOSE; fix bin_file overrun.
v607 7/19/22 Update Unicode tables.
v608 7/22/22 Fix highlighting on colored text boundaries.
v609 11/10/22 Add LESSUTFCHARDEF; fix overstrike color bug;
fix procfs bug; fix signal race.
v610 11/14/22 Update Unicode tables; fix again-search after filter;
improve ^X to interrupt F command.
v611 11/16/22 Fix EOF bug related to ^X change.
v612 11/18/22 Fix more bugs related to ^X change.
v613 11/28/22 Even more ^X issues.
v614 11/28/22 Add ^X to wait message.
v615 11/30/22 Add --no-vbell option.
v616 12/9/22 Don't open tty as input file without -f.
v617 12/10/22 Support poll on newer versions of MacOS.
v618 12/29/22 Add --no-search-headers option; use C89 function definitions.
v619 12/30/22 Fix bug using 'n' before '/'.
v620 1/12/23 Add --modelines option; add --intr option;
add subpattern coloring.
v621 1/15/23 Add --wordwrap option; add LESS_LINES & LESS_COLUMNS.
v622 1/27/23 Add --show-preproc-errors option.
v623 2/2/23 Add # command; add ^S search modifier.
v624 2/11/23 Add --proc-backspace, --proc-tab and --proc-return options.
v625 2/16/23 Minor fixes.
v626 2/19/23 Fix rare crash in add_attr_normal.
v627 2/19/23 Doc.
v628 2/20/23 Don't require newline after +&...
v629 2/26/23 Delay "waiting for data" message for 500 ms.
v630 3/18/23 Add LESS_DATA_DELAY.
v631 3/26/23 Fix input of dead keys on Windows.
v632 4/6/23 Make lesstest work on MacOS; minor fixes.
v633 5/3/23 Fix build on systems with ncurses/termcap.h or ncursesw/termcap.h.
v634 5/29/23 Allow program piping into less to access tty;
fix search modifier ^E after ^W.
v635 6/2/23 Fix crash with ! search modifier.
v636 6/18/23 Fix -D in MS-DOS build; fix mouse wheel in MS-DOS build.
v637 6/28/23 Fix early EOF when SIGWINCH is received.
v638 6/29/23 Fix compile error with ECHONL.
v639 6/29/23 Fix SIGWINCH while reading tty.
v640 7/10/23 Add lesstest to release.
v641 7/10/23 Fix release.
v642 7/10/23 Fix release.
v643 7/20/23 Fix crash on Windows with -o.
v644 9/16/23 Improve ^C on non-terminated pipe; fix crash when files are
deleted; support large files and non-BMP chars on Windows;
fix # bug; don't filter header lines; fix shifting long lines;
add --match-shift.
v645 11/5/23 Default Windows charset is utf-8; update Unicode tables;