xref: /freebsd-11.0-release/contrib/less/NEWS

                     NEWS about less

======================================================================

  For the latest news about less, see the "less" Web page:
      http://www.greenwoodsoftware.com/less
  You can also download the latest version of less from there.

  To report bugs, suggestions or comments, send email to bug-less@gnu.org

======================================================================

	Major changes between "less" versions 458 and 481

* Don't overwrite history file; just append to it.

* New command ESC-G goes to end of currently buffered data in a pipe.

* Disable history feature when compiled with LESSHISTFILE set to "-".

* In more-compatible mode, make the -p option apply to every file opened,
  not just the first one.

* In more-compatible mode, change the -e option to work like -E, not -EF.

* Treat multiple CRs before LF are like one CR (all the CRs are hidden).

* Allow "extra" string in lesskey file to append to a multi-char command
  (like a search pattern), without executing the command.

* Ignore -u/-U setting while viewing help file, so that 
  underline and bold chars are displayed correctly.

* Improve detection of "binary" files in UTF-8 mode.

* Fix bug with ++ commands.

* Fix bug where prompt was sometimes not displayed with +G.

* Fix possible memory corruption 

* Fix bugs and improve performance in ampersand filtering.

* Automate construction of Unicode tables from Unicode database.

* Allow %% escape sequence in LESSOPEN variable.

======================================================================

	Major changes between "less" versions 451 and 458

* Allow backslash escaping of metacharacters in LESS environment variable
  after the --use-backslash option.

* Don't quit if syntax errors are found in command line options.

* Increase sizes of some internal buffers.

* Fix configure bug with --with-regex=none.

* Fix crash with "stty rows 0".

* Fix Win32 attribute display bug.

* Fix display bug when using up/down arrow on the command line.

======================================================================

	Major changes between "less" versions 444 and 451

* Add ESC-F command to keep reading data until a pattern is found.

* Use exit code of LESSOPEN script if LESSOPEN starts with "||".

* When up/down arrow is used on the command line immediately after
  typing text, the next command starting with that text is found.

* Add support for GNU regex.

* Add configure option --with-regex=none and fix compile errors
  when compiling with no regex library.

* Fix bugs handling SGR sequences in Win32.

* Fix possible crashes caused by malformed LESSOPEN or 
  LESSCLOSE variables.

* Fix bug highlighting text which is discontiguous in the file 
  due to backspace processing.

* Fix bug in displaying status column when scrolling backwards 
  with -J and -S in effect.

======================================================================

	Major changes between "less" versions 443 and 444

* Fix bug in unget handling that can cause strange effects on the
  command line.

* Remove vestiges of obsolete -l option that can cause a crash.

======================================================================

	Major changes between "less" versions 436 and 443

* Change search behavior such that when a search is given an explicit 
  pattern, the entire displayed screen is included in the search and 
  not just the portion after the target line.

* Add -A option to change search behavior to the old way: only
  the portion of the screen after the target line is searched.

* Add %F formatting to prompt strings, replaced by the last component
  of the input file.

* Control-G while editing a command exits the command.

* Less now exits with status 2 if control-C is pressed and -K is in effect.

* Fix "ungetc overflow" when passing long commands via the -p option.

* Fix bug in using line filtering via the & command 
  in combination with -i and -I.

* Fix bug in handling negative arguments to the -j option.

* Fix bug in handling %t in prompt strings.

* Improve handling of long option names.

* Improve percentage calculation for very large files.

======================================================================

	Major changes between "less" versions 429 and 436

* Don't pass "-" to non-pipe LESSOPEN unless it starts with "-".

* Allow a fraction as the argument to the -# (--shift) option.

* Fix highlight bug when underlined/overstruck text matches at end of line.

* Fix non-regex searches with ctrl-R.

======================================================================

	Major changes between "less" versions 424 and 429

* LESSOPEN pipe will now be used on standard input, if the LESSOPEN
  environment variable begins with "|-".

* The -D option with one number now means use the normal background color.

* Don't change permissions on history file if it is not a regular file.

* Fix non-ANSI-compliant code that caused problems with some compilers.

* Fix binary file detection in UTF-8 mode.

* Fix display problems with long lines on "ignaw" terminals.

* Fix problem interrupting the line number calculation for initial prompt.

* Fix SGR emulation when dealing with multiple attributes (eg. bold+underline).

* Fix highlight bug when searching for underlined/overstruck text.

======================================================================

	Major changes between "less" versions 418 and 424

* New "&" command allows filtering of lines based on a pattern.

* Status column now displays a search match, even if the matched
  string is scrolled off screen because -S is in effect.

* Improve behavior of -F option.

* Allow CSI character (0x9B) to work in UTF-8 mode.

* Output carriage return at startup in case terminal doesn't default
  to column 1.

* Fix bug in '' (quote, quote) command after G command.

======================================================================

	Major changes between "less" versions 416 and 418

* Color escape sequences are now supported in WIN32 build.

* Makefile now uses EXEEXT feature of autoconf.

* Fix search bug when using -R and text contains ANSI color escape sequences.

* Fix crash when using -r with UTF-8 text containing 0x9B bytes.

* Fix display bug when using ' command to move less than one page forward.

* Update GPL to version 3.

======================================================================

	Major changes between "less" versions 409 and 416

* New --follow-name option makes F command follow the name of a file
  rather than the file descriptor if an open file is renamed.

* Make searching with -i/-I work correctly with non-ASCII text.

* Fix DJGPP build.

======================================================================

	Major changes between "less" versions 406 and 409

* Support CSI escape sequences, like SGR escape sequences.

* Fix bug which caused screen to fail to repaint when window is resized.

* Fix bug in using -i and -I flags with non-ASCII text.

* Fix configure bug on systems which don't support langinfo.h.

* Fix crash when searching text containing certain invalid UTF-8 sequences.

======================================================================

	Major changes between "less" versions 394 and 406

* Allow decimal point in number for % (percent) command.

* Allow decimal point in number for -j option (fraction of screen height).

* Make n command fetch previous pattern from history file on first search.

* Don't rewrite history file if it has not changed.

* Don't move to bottom of screen on first page.

* Don't output extraneous newlines, so copy & pasting lines from the
  output works better.

* The -c option has been made identical with the -C option.

* Allow "/dev/null" as synomym for "-" in LESSHISTFILE to indicate
  that no history file should be used.

* Search can now find text which follows a null byte, if the PCRE
  library is used, or if no-regex searching (ctrl-R) is used.

* Better compatibility with POSIX more specification.

* Make -f work for directories.

* Make "t" cmd traverse tags in the correct order.

* Allow a few binary characters in the input file before warning
  that the file is binary.

* Don't warn that file is binary if it merely contains ANSI color sequences
  and -R is in effect.

* Update Unicode character tables.

* Support DESTDIR in Makefile.

* Fix bug when filename contains certain shell metacharacters such as "$".

* Fix bug when resizing the window while waiting for input from a pipe.

* Fix configure bugs.

======================================================================

	Major changes between "less" versions 382 and 394

* Add history file to save search and shell command history between
  invocations of less.

* Improve behavior of history list for search and shell commands.

* Add -K (or --quit-on-intr) option to make less exit immediately on ctrl-C.

* Improve handling of UTF-8 files and commands, including better
  line wrapping and handling double-width chars.

* Added LESSUTFBINFMT environment variable to control display of
  non-printable characters in a UTF-8 file.

* Add --with-secure option to configure, to make it easier to
  build a secure version of less.

* Show search matches in the status column even if search highlights
  are disabled via the -G option or the ESC-u command.

* Improve performance when the file contains very long lines.

* Add "windows" charset.

* Add man page for lessecho.

* Add support for erase2 character, treated same as erase.

* Use ASCII lowercase/uppercase logic when operating on the command line.

* Update makefile for Borland C++ 5.5.1.

* Fix bug in calculating number of pages for %D prompt.

* Fix bug in handling tag file error.

* Fix obscure bug if input file is deleted while viewing help.

* Fix bug handling filenames which include square brackets.

* Fix possible buffer overflow in "global" tag search.

* Fix possible buffer overflow in usage of LESSOPEN and LESSCLOSE.

* Fix buffer overflow in reverse search.

======================================================================

	Major changes between "less" versions 381 and 382

* Removed some old copyrighted code.
  This probably breaks OS/9 support.

======================================================================

	Major changes between "less" versions 378 and 381

* New -L option to disable LESSOPEN processing.

* Further support for large (64 bit) file addressing.
  Large file support is now set up by the configure script.

* Use autoconf 2.54.
  Replace configure.in, acconfig.h, defines.h.top with configure.ac.

* Overstriking underscore with underscore is now bold or underlined 
  depending on context.

* Use only 7 spaces for line numbers in -N mode, if possible.

* Fix some bugs in handling overstriking in UTF-8 files.

* Fix some nroff issues in the man page.

======================================================================

	Major changes between "less" versions 376 and 378

* Bug fixes:
  Default buffer space is now 64K as documented.
  Search highlighting works properly when used with -R.
  Windows version works properly when input file contains carriage returns.
  Clean up some compiler warnings.

======================================================================

	Major changes between "less" versions 358 and 376

* -x option can now specify multiple variable-width tab stops.

* -X option no longer disables keypad initialization.
  New option --no-keypad disables keypad initialization.

* New commands t and T step through multiple tag matches.
  Added support for "global(1)" tags
  (see http://www.gnu.org/software/global/global.html).

* New prompt style set by option -Pw defines the message printed 
  while waiting for data in the F command.

* System-wide lesskey file now defaults to sysless in etc directory 
  instead of .sysless in bin directory.
  Use "configure --sysconfdir=..." to change it.
  (For backwards compatibility, .sysless in bin is still recognized.)

* Pressing RightArrow or LeftArrow while entering a number now shifts
  the display N columns rather than editing the number itself.

* Status column (enabled with -J) now shows search results.

* Windows version sets window title.

* Default LESSCHARSET for MS-DOS versions is now "dos".

* Searching works better with ANSI (SGR) escape sequences.
  ANSI color escape sequences are now supported in the MS-DOS (DJGPP) version.

* Improved performance in reading very large pipes.

* Eliminated some dependencies on file offets being 32 bits.

* Fixed problems when viewing files with very long lines.

* Fixed overstriking in UTF-8 mode, and overstriking tabs.

* Improved horizontal shifting of text using -R option with ANSI color.

* Improved handling of filenames containing shell metacharacters.

* Some fixes for EBCDIC systems.

* Some fixes for OS/2 systems.

======================================================================

	Major changes between "less" versions 354 and 358

* Add -J (--status-column) option to display a status column.

* Add -# (--shift) option to set default horizontal shift distance.
  Default horizontal shift distance is now one-half screen width.

* Horizontal shifting does not shift line numbers if -N is in effect.

* Horizontal shifting acts as though -S were set, to avoid confusion.

======================================================================


	Major changes between "less" versions 352 and 354

* Allow space after numeric-valued command line options.

* Fix problem with configuring terminal libraries on some systems.

* Add support for PCRE regular expression library.

* Add --with-regex option to configure to allow manually selecting
  a regular expression library.

* Fix bug compiling with SECURE = 1.

======================================================================


	Major changes between "less" versions 346 and 352

* Enable UTF-8 if "UTF-8" appears in locale-related environment variables.

* Add --with-editor option to configure script.

* The -M prompt and = message now show the top and bottom line number.

* Fix bug in running the editor on a file whose name contains quotes, etc.

* Fix bug in horizontal scrolling of long lines.

* Fix bug in doing :d on a file which contains marks.

* Fix bug causing cleared lines to sometimes be filled with standout, 
  bold, underline, etc. on certain terminals.

* Fixes for MS-DOS (DJGPP) version.

======================================================================


	Major changes between "less" versions 340 and 346

* The UTF-8 character set is now supported.

* The default character set is now latin1 rather than ascii.

* New option -R (--RAW-CONTROL-CHARS) is like -r but handles 
  long (wrapped) lines correctly, as long as the input contains only 
  normal text and ANSI color escape sequences.

* New option -F (--quit-if-one-screen) quits if the text fits on
  the first screen.

* The -w option now highlights the target line of a g or p command.

* A system-wide lesskey file is supported (LESSKEY_SYSTEM).

* New escape for prompt strings: %c is replaced by column number.

* New escape for prompt strings: %P is replaced by percentage into
  file, based on line number rather than byte offset.

* HOME and END keys now jump to beginning of file or end of file.

======================================================================


	Major changes between "less" versions 337 and 340

* Command line options for less may now be given in either the old 
  single-letter form, or a new long name form (--option-name).
  See the less man page or "less --help" for the list of long option names.

* Command line options for lesskey may now be given in a new long name
  form.  See the lesskey man page for the list of long option names.

* New command -- toggles an option using the long option name.

* New command __ queries an option using the long option name.

* The old -- command is renamed as -!.

* If a ^P is entered between the dash and the option letter of the -
  command, the message describing the new setting is suppressed.

* Lesskey files may now contain \k escape sequences to represent the
  "special" keys (arrows, PAGE-UP/PAGE-DOWN, HOME, END, INSERT, DELETE).

* New command :d removes the current file from the list of files.

* New option -~ (like -w before version 335)
  suppresses tildes after end-of-file.

* Less is now released under the GNU General Public License.

======================================================================


	Major changes between "less" versions 335 and 337

* Fixed bugs in "make install".

======================================================================


	Major changes between "less" versions 332 and 335

* The old -w flag (suppress tildes after end-of-file) has been removed.

* New -w flag highlights the first new line after a forward-screen.

* New -W flag highlights the first new line after any forward movement.

* Window resize works even if LINES and/or COLUMNS environment 
  variables are incorrect.

* New percent escapes for prompt strings:
  %d is replaced by the page number, and
  %D is replaced by the number of pages in the file.

* Added charsets "iso8859" and "ebcdic".

* In Windows version, uses HOMEDRIVE and HOMEPATH if HOME is not defined.

* Fixed some bugs causing incorrect display on DOS/Windows.

======================================================================


	Major changes between "less" versions 330 and 332

* Filenames from the command line are entered into the command history,
  so UPARROW/DOWNARROW can be used to retrieve them from the :e command.

* Now works correctly on Windows when using a scrolling terminal
  window (buffer larger than display window).

* On Windows, now restores the console screen on exit.  
  Use -X to get the old behavior.

* Fixed bug on Windows when CAPS-LOCK or NUM-LOCK is pressed.

* Fixed bug on Windows when piping output of an interactive program.

* Fixed bug in tags file processing when tags file has DOS-style
  line terminators (CR/LF).

* Fixed compilation problem on OS/2.

======================================================================


	Major changes between "less" versions 321 and 330

* Now supports filenames containing spaces (in double quotes).
  New option -" can be used to change the quoting characters.

* In filename completion, a slash is appended to a directory name.
  If the environment variable LESSSEPARATOR is set, the value of
  that variable, rather than a slash, is appended.

* LeftArrow and RightArrow are same as ESC-[ and ESC-].

* Added commands ESC-( and ESC-), same as ESC-[ and ESC-].

* A "quit" command defined in a lesskey file may now have an "extra" 
  string, which is used to return an exit code from less when it quits.

* New environment variables LESSMETACHARS and LESSMETAESCAPE provide
  more control over how less interfaces to the shell.

* Ported to Microsoft Visual C compiler for Windows.

* Ported to DJGPP compiler for MS-DOS.

* Bug fixes.

======================================================================


	Major changes between "less" versions 291 and 321

* Command line at bottom of screen now scrolls, so it can be longer 
  than the screen width.

* New commands ESC-] and ESC-[ scroll the display horizontally.

* New command ESC-SPACE scrolls forward a full screen, even if it
  hits end-of-file.

* Alternate modifiers for search commands: ^N is same as !,
  ^F is same as @, and ^E is same as *.

* New modifier for search commands: ^K means highlight the matches
  currently on-screen, but don't move to the first match.

* New modifier for search commands: ^R means don't use regular
  expressions in the search.

* Environment variable LESSKEY gives name of default lesskey file.

* Environment variable LESSSECURE will force less to run in
  "secure" mode.

* Command line argument "--" signals that the rest of the arguments
  are files (not option flags).

* Help file (less.hlp) is no longer installed.  Help text is now 
  embedded in the less executable itself.

* Added -Ph to change the prompt for the help text.
  Added -Ps to change the default short prompt (same as plain -P).

* Ported to the Borland C compiler for MS-DOS.

* Ported to Windows 95 & Windows NT.

* Ported to OS-9.

* Ported to GNU Hurd.

======================================================================


	Major changes between "less" versions 290 and 291

* Less environment variables can be specified in lesskey files.

* Fixed MS-DOS build.

======================================================================


	Major changes between "less" versions 278 and 290

* Accepts GNU-style options "--help" and "--version".

* OS/2 version looks for less.ini in $HOME before $INIT and $PATH.

* Bug fixes

======================================================================


	Major changes between "less" versions 252 and 278

* A LESSOPEN preprocessor may now pipe the converted file data to less,
  rather than writing it to a temporary file.

* Search pattern highlighting has been fixed.  It now highlights 
  reliably, even if a string is split across two screen lines,
  contains TABs, etc.

* The -F flag (which suppress search highlighting) has been changed 
  to -G.  A new flag, -g, changes search highlighting to highlight 
  only the string found by the last search command, instead of all 
  strings which match the last search command.

* New flag -I acts like -i, but ignores case even if the search 
  pattern contains uppercase letters.

* Less now checks for the environment variable VISUAL before EDITOR.

* Ported to OS/2.

======================================================================


	Major changes between "less" versions 237 and 252

* Changes in line-editing keys:
  The literal key is now ^V or ^A rather than \ (backslash).
  Filename completion commands (TAB and ^L) are disabled 
  when typing a search pattern.

* Line-editing command keys can be redefined using lesskey.

* Lesskey with no input file defaults to $HOME/.lesskey
  rather than standard input.

* New option -V displays version number of less.

* New option -V displays version number of lesskey.

* Help file less.hlp is now installed by default in /usr/local/share 
  rather than /usr/local/lib.


======================================================================


	Major changes between "less" versions 170 and 237

* By popular demand, text which matches the current search pattern
  is highlighted.  New -F flag disables this feature.

* Henry Spencer's regexp.c is now included, for systems which do not
  have a regular expression library.
  regexp.c is Copyright (c) 1986 by University of Toronto.

* New line-editing keys, including command history (arrow keys) and 
  filename completion (TAB).

* Input preprocessor allows modification of input files (e.g. uncompress)
  via LESSOPEN/LESSCLOSE environment variables.

* New -X flag disables sending termcap "ti" and "te" (initialize and
  deinitialize) strings to the terminal. 

* Changing -i from within less now correctly affects a subsequent
  repeated search.  

* Searching for underlined or overstruck text now works when the -u
  flag is in effect, rather than the -i flag.

* Use setlocale (LANG and LC_CTYPE environment variables) to determine
  the character set if LESSCHARSET/LESSCHARDEF are not set.

* The default format for displaying binary characters is now standout
  (reverse video) rather than blinking.  This can still be changed by
  setting the LESSBINFMT environment variable.

* Use autoconf installation technology.

* Ported to MS-DOS.

        ********************************
          Things that may surprise you
        ********************************

* When you enter text at the bottom of the screen (search string, 
  filename, etc.), some keys act different than previously.  
  Specifically, \ (backslash), ESC, TAB, BACKTAB, and control-L 
  now have line editing functions.

* Some previous unofficial versions of less were able to display
  compressed files.  The new LESSOPEN/LESSCLOSE feature now provides
  this functionality in a different way.

* Some previous unofficial versions of less provided a -Z flag to 
  set the number of lines of text to retain between full screen scrolls.
  The -z-n flag (that is, -z with a negative number) provides this 
  functionality.


======================================================================


	Major changes between "less" versions 123 and 170

* New option -j allows target lines to be positioned anywhere on screen.

* New option -S truncates displayed line at the screen width,
  rather than wrapping onto the next line.

* New option -y limits amount of forward scroll.

* New option -T specifies a "tags" file.

* Non-printable, non-control characters are displayed in octal.
  Such characters, as well as control characters, are displayed 
  in blinking mode.

* New command -+ sets an option to its default.
* New command -- sets an option to the opposite of its default.

* Lesskey file may have a string appended to a key's action,
  which acts as though typed in after the command.

* New commands ESC-^F and ESC-^B match arbitrary types of brackets.

* New command F monitors a growing file (like "tail -f").

* New command | pipes a section of the input file into a shell command.

* New command :x directly jumps to a file in the command line list.

* Search commands have been enhanced and reorganized:
	n	Repeat search, same direction.
	N	Repeat search, opposite direction.
	ESC-/	Search forward thru file boundaries
	ESC-?	Search backward thru file boundaries
	ESC-n	Repeat search thru file boundaries, same direction.
	ESC-N	Repeat search thru file boundaries, opposite direction.
  Special character * causes search to search thru file boundaries.
  Special character @ causes search to begin at start/end of file list.

* Examining a new file adds it to the command line list.
  A list of files, or an expression which matches more than one file,
  may be examined; all of them are added to the command line list.

* Environment variables LESSCHARSET and LESSCHARDEF can define
  a non-ASCII character set.

* Partial support for MSDOS, including options -R for repainting screen
  on quit, -v/-V to select video mode, and -W to change window size.


======================================================================


	Major changes between "less" versions 97 and 123

* New option (-N) causes line numbers to be displayed in the
  text of the file (like vi "set nu").

* New option (-?) prints help message immediately.

* New option (-r) displays "raw" control characters, without
  mapping them to ^X notation.

* New option (-f) forces less to open non-regular files
  (directories, etc).

* New option (-k) can be used to specify lesskey files by name.

* New option (-y) can be used to set a forward scroll limit
  (like -h sets a backward scroll limit).

* File marks (set by the m command) are now preserved when a new
  file is edited.  The ' command can thus be used to switch files.

* New command ESC-/ searches all files (on the command line) 
  for a pattern.

* New command ESC-n repeats previous search, spanning files.

* The N command has been changed to repeat the previous search
  in the reverse direction.  The old N command is still available 
  via :n.

* New command ESC-N repeats previous search in the reverse
  direction and spanning files.

* 8 bit characters are now supported.  A new option (-g) can be 
  used to strip off the eighth bit (the previous behavior).

* Options which take a following string (like -t) may now
  optionally have a space between the option letter and the string.

* Six new commands { } ( ) [ and ] can be used to match
  brackets of specific types, similar to vi % command.

* New commands z and w move forward/backward one window and
  simultaneously set the window size.

* Prompt string expansion now has %L for line number of the last
  line in the file, and %E for the name of the editor.
  Also, % escapes which refer to a line (b=bottom, t=top, etc.)
  can use j for the jump target line.

* New environment variable LESSEDIT can be used to tailor the
  command string passed to the editor by the v command.

* Examining a file which was previously examined will return
  to the same position in the file.

* A "%" is expanded to the current filename and a "#" to the 
  previous filename, in both shell commands and the E command.
  (Previously % worked only in shell commands and # worked 
  only in the E command.)

* New command ":ta" is equivalent to "-t".

* New command "s" is equivalent to "-l".

* The - command may be followed by "+X" to revert to the default
  for option X, or "-X" to get the opposite of the default.

* Lesskey files may now include characters after the action as
  extra input to be parsed after the action; for example:
  "toggle-option X" to toggle a specific option X.