- Announcing ncurses 5.5
+ Announcing ncurses 6.2
+
+Overview
The ncurses (new curses) library is a free software emulation of
- curses in System V Release 4.0, and more. It uses terminfo format,
- supports pads and color and multiple highlights and forms characters
- and function-key mapping, and has all the other SYSV-curses
- enhancements over BSD curses.
+ curses in System V Release 4.0 (SVr4), and more. It uses terminfo
+ format, supports pads and color and multiple highlights and forms
+ characters and function-key mapping, and has all the other SVr4-curses
+ enhancements over BSD curses. SVr4 curses became the basis of X/Open
+ Curses.
In mid-June 1995, the maintainer of 4.4BSD curses declared that he
- considered 4.4BSD curses obsolete, and encouraged the keepers of Unix
+ considered 4.4BSD curses obsolete, and encouraged the keepers of unix
releases such as BSD/OS, FreeBSD and NetBSD to switch over to ncurses.
- The ncurses code was developed under GNU/Linux. It has been in use for
- some time with OpenBSD as the system curses library, and on FreeBSD
- and NetBSD as an external package. It should port easily to any
- ANSI/POSIX-conforming UNIX. It has even been ported to OS/2 Warp!
+ Since 1995, ncurses has been ported to many systems:
+ * It is used in almost every system based on the Linux kernel (aside
+ from some embedded applications).
+ * It is used as the system curses library on OpenBSD, FreeBSD and
+ MacOS.
+ * It is used in environments such as Cygwin and MinGW. The first of
+ these was EMX on OS/2 Warp.
+ * It is used (though usually not as the system curses) on all of the
+ vendor unix systems, e.g., AIX, HP-UX, IRIX64, SCO, Solaris,
+ Tru64.
+ * It should work readily on any ANSI/POSIX-conforming unix.
The distribution includes the library and support utilities, including
- a terminfo compiler tic(1), a decompiler infocmp(1), clear(1),
- tput(1), tset(1), and a termcap conversion tool captoinfo(1). Full
- manual pages are provided for the library and tools.
-
- The ncurses distribution is available via anonymous FTP at the GNU
- distribution site [1]ftp://ftp.gnu.org/gnu/ncurses/ .
- It is also available at [2]ftp://invisible-island.net/ncurses/ .
-
- Release Notes
-
- This release is designed to be upward compatible from ncurses 5.0
- through 5.4; very few applications will require recompilation,
- depending on the platform. These are the highlights from the
- change-log since ncurses 5.4 release.
-
- Interface changes:
- * terminfo installs "xterm-new" as "xterm" entry rather than
- "xterm-old" (aka xterm-r6).
- * terminfo data is installed using the tic -x option (few systems
- still use ncurses 4.2).
- * modify C++ binding to work with newer C++ compilers by providing
- initializers and using modern casts. Old-style header names are
- still used in this release to allow compiling with not-so-old
- compilers.
- * modify parameter type in c++ binding for insch() and mvwinsch() to
- be consistent with underlying ncurses library (was char, is
- chtype).
- * change NCursesWindow::err_handler() to a virtual function.
- * form and menu libraries now work with wide-character data.
- Applications which bypassed the form library and manipulated the
- FIELD.buf data directly will not work properly with libformw,
- since that no longer points to an array of char. The
- set_field_buffer() and field_buffer() functions translate to/from
- the actual field data.
- * add symbol to curses.h which can be used to suppress include of
- stdbool.h, e.g.,
- #define NCURSES_ENABLE_STDBOOL_H 0
- #include <curses.h>
-
- * change SP->_current_attr to a pointer, adjust ifdef's to ensure
- that libtinfo.so and libtinfow.so have the same ABI. The reason
- for this is that the corresponding data which belongs to the
- upper-level ncurses library has a different size in each model.
- * winnstr() now returns multibyte character strings for the
- wide-character configuration.
- * assume_default_colors() no longer requires that
- use_default_colors() be called first.
- * data_ahead() now works with wide-characters.
- * slk_set() and slk_wset() now accept and store multibyte or
- multicolumn characters.
- * start_color() now returns OK if colors have already been started.
- start_color() also returns ERR if it cannot allocate memory.
- * pair_content() now returns -1 for consistency with init_pair() if
- it corresponds to the default-color.
- * unctrl() now returns null if its parameter does not correspond to
- an unsigned char.
-
- New features and improvements:
- * library
- + environment variable NCURSES_NO_UTF8_ACS supports
- miscellaneous terminal emulators which ignore alternate
- character set escape sequences when in UTF-8 mode.
- + modify initialization of key lookup table so that if an
- extended capability (tic -x) string is defined, and its name
- begins with 'k', ncurses will automatically treat it as a
- key.
- + change GPM initialization, using dl library to load it
- dynamically at runtime.
- + form, menu and panel libraries support debug-tracing.
- * add NCURSES-Programming-HOWTO.html by Pradeep Padala (see
- http://tldp.org/HOWTO/NCURSES-Programming-HOWTO/).
- * programs:
- * infocmp:
- + The -i option now matches 8-bit controls against its table
- entries, e.g., so it can analyze the xterm-8bit entry.
- + add "-x" option to infocmp like tic's "-x", for use in "-F"
- comparisons. This modifies infocmp to only report extended
- capabilities if the -x option is given, making this more
- consistent with tic. Some scripts may break, since infocmp
- previous gave this information without an option.
- * tic:
- + modify termcap-parsing to retain 2-character aliases at the
- beginning of an entry if the "-x" option is used in tic.
- + filter out long extended names when translating to termcap
- format. Only two characters are permissible for termcap
- capability names.
- + correct translation of "%%" in terminfo format to termcap,
- e.g., using "tic -C".
- + modify the "-c -v" options to ignore delays when comparing
- strings. Also modify it to ignore a canceled sgr string,
- e.g., for terminals which cannot properly combine attributes
- in one control sequence.
- + add a check for improperly ended strings, i.e., where a
- following line begins in column 1.
- + add a check in tic for terminfo entries having an sgr0 but no
- sgr string. This confuses Tru64 and HPUX curses when combined
- with color, e.g., making them leave line-drawing characters
- in odd places.
- + add check (with debug configuration) that provides about the
- runtime changes that would be made to sgr0 for termcap
- applications.
- * tset:
- + add -c and -w options to allow user to suppress ncurses'
- resizing of the terminal emulator window in the special case
- where it is not able to detect the true size.
-
- Major bug fixes:
- * improve logic in tgetent() which adjusts the termcap "me" string
- to work with ISO-2022 string used in xterm-new. This is a feature
- that was incompletely implemented in ncurses 5.3. ncurses attempts
- to provide termcap clients with the portion of the sgr0 (termcap
- "me") string that does not reset line-drawing.
- * cells in the WINDOW which are continuations of a multicolumn
- character are encoded differently, making repainting more
- reliable.
- * amend change to setupterm() in ncurses 5.4 (20030405) which would
- reuse the value of cur_term if the same output was selected. This
- now reuses it only when setupterm() is called from tgetent(),
- which has no notion of separate SCREENs. Note that tgetent() must
- be called after initscr() or newterm() to use this feature.
- * make setcchar() now works when its wchar_t* parameter is pointing
- to a string which contains more data than can be converted.
- * win_wchnstr() now works for more than one cell.
- * resizeterm() now processes all levels of window hierarchy.
- * disable GPM mouse support when $TERM happens to be prefixed with
- "xterm". Gpm_Open() would otherwise assert that it can deal with
- mouse events in this case.
- * add SP->_screen_acs_map[], used to ensure that mapping of missing
- line-drawing characters is handled properly. For example,
- ACS_DARROW is absent from xterm-new, and it was coincidentally
- displayed the same as ACS_BTEE.
-
- Portability:
- * configure script:
- + new options:
-
- --enable-largefile
- set compiler and linker flags to use largefile
- support.
-
- --enable-ext-colors
- Allow encoding of 256 foreground and background
- colors, e.g., with the xterm-256color or
- xterm-88color terminfo entries. This requires ABI 6
- because it changes the size of cchar_t.
-
- --enable-ext-mouse
- This defines NCURSES_MOUSE_VERSION 2, and modifies
- the encoding of mouse events to support wheel mice,
- which may transmit buttons 4 and 5. This works with
- xterm and similar terminal emulators. This requires
- ABI 6 because it changes the encoding of mouse
- events.
-
- --with-chtype
- overriding of the non-LP64 model's use of chtype
-
- --with-mmask-t
- overriding of the non-LP64 model's use of mmask_t
-
- --without-xterm-new
- Installs "xterm-old" as the "xterm" entry of the
- terminfo database.
-
- + The --with-termlib option now accepts a value which sets the
- name of the terminfo library. This would allow a packager to
- build libtinfow.so renamed to coincide with libtinfo.so
- + fixes/improvements for cross-compiling:
- o suppress $suffix in misc/run_tic.sh when
- cross-compiling. This allows cross-compiles to use the
- host's tic program to handle the "make install.data"
- step.
- o correct BUILD_CPPFLAGS substitution in
- ncurses/Makefile.in, to allow cross-compiling from a
- separate directory tree.
- * library:
- + add ifdef's for _LP64 in curses.h to avoid using wasteful
- 64-bits for chtype and mmask_t, but add configure option
- --disable-lp64 in case anyone used that configuration.
- + modify C++ binding to use some C internal functions to make
- it compile properly on Solaris (and other platforms).
- + remove check in newwin() that prevents allocating windows
- that extend beyond the screen (Solaris does this).
- + check for nl_langinfo(CODESET), use it if available. This
- replaces ad hoc tests of environment variables to check if
- the terminal is setup for UTF-8 encoding. Applications which
- do not call setlocale() should be corrected, to make them
- work properly with UTF-8 encoding.
- In particular, applications which assume (and do not call
- setlocale()) that Latin-1 codes are printable will no longer
- work in a UTF-8 locale since the ad hoc check of environment
- variables to see if the locale was UTF-8 is not used when
- nl_langinfo(CODESET) is available.
- + use setlocale() to query the program's current locale rather
- than using getenv(). This supports applications which rely
- upon legacy treatment of 8-bit characters when the locale is
- not initialized.
-
- Features of Ncurses
-
- The ncurses package is fully compatible with SVr4 (System V Release 4)
- curses:
- * All 257 of the SVr4 calls have been implemented (and are
- documented).
- * Full support for SVr4 curses features including keyboard mapping,
- color, forms-drawing with ACS characters, and automatic
- recognition of keypad and function keys.
- * An emulation of the SVr4 panels library, supporting a stack of
- windows with backing store, is included.
- * An emulation of the SVr4 menus library, supporting a uniform but
- flexible interface for menu programming, is included.
- * An emulation of the SVr4 form library, supporting data collection
- through on-screen forms, is included.
- * Binary terminfo entries generated by the ncurses tic(1)
- implementation are bit-for-bit-compatible with the entry format
- SVr4 curses uses.
- * The utilities have options to allow you to filter terminfo entries
- for use with less capable curses/terminfo versions such as the
- HP/UX and AIX ports.
+ * captoinfo, a termcap conversion tool
+ * clear, utility for clearing the screen
+ * infocmp, the terminfo decompiler
+ * tabs, set tabs on a terminal
+ * tic, the terminfo compiler
+ * toe, list (table of) terminfo entries
+ * tput, utility for retrieving terminal capabilities in shell
+ scripts
+ * tset, to initialize the terminal
+
+ Full manual pages are provided for the library and tools.
+
+ The ncurses distribution is available at ncurses' homepage:
+
+ ftp://ftp.invisible-island.net/ncurses/ or
+ https://invisible-mirror.net/archives/ncurses/ .
+
+ It is also available via anonymous FTP at the GNU distribution site
+
+ ftp://ftp.gnu.org/gnu/ncurses/ .
+
+Release Notes
+
+ These notes are for ncurses 6.2, released February 12, 2020.
+
+ This release is designed to be source-compatible with ncurses 5.0
+ through 6.1; providing extensions to the application binary interface
+ (ABI). Although the source can still be configured to support the
+ ncurses 5 ABI, the reason for the release is to reflect improvements
+ to the ncurses 6 ABI and the supporting utility programs.
+
+ There are, of course, numerous other improvements, listed in this
+ announcement.
+
+ The most important bug-fixes/improvements dealt with user-defined
+ capabilities in terminal descriptions. The release notes also mention
+ some other bug-fixes, but are focused on new features and improvements
+ to existing features since ncurses 6.1 release.
+
+ Library improvements
+
+ New features
+
+ There are several new features:
+ * O_EDGE_INSERT_STAY tells the form library to optionally delay
+ cursor movement on a field edge/boundary
+ * O_INPUT_FIELD extension to form library allows a dynamic field to
+ shrink if the new limit is smaller than the current field size.
+ * added exit_curses and exit_terminfo to replace internal symbols
+ for leak-checking.
+ * added curses_trace, to replace trace().
+
+ Additionally, to improve performance other changes (and extensions)
+ are provided in this release:
+ * mouse decoding now handles shift/control/alt logic when decoding
+ xterm's 1006 mode
+ * ncurses now defines a limit for wgetnstr, wgetn_wstr when length
+ is negative or "too large".
+ * reordered loop-limit checks in winsnstr in case the string has no
+ terminating null and only the number of characters is used.
+ * there is now no buffer-size limit when reading the $TERMCAP
+ variable.
+ * the $TERMCAP variable may be interpreted as a fallback to a
+ terminfo entry
+ * mvcur now decides whether to use hard-tabs, using xt, tbc and hts
+ as clues.
+ * extended colors are improved by modifying an internal call to
+ vid_puts to pass extended color pairs e.g., from tty_update.c and
+ lib_mvcur.c
+ * the initialization functions now avoid relying upon persistent
+ data for the result from getenv
+ * scrolling is improved:
+ + a limit check in newline_forces_scroll handles the case where
+ the row is inside scroll-margins, but not at the end.
+ + improved loop limits in _nc_scroll_window handle a case where
+ the scrolled data is a pad which is taller than the window.
+
+ Other improvements
+
+ These are revised features:
+ * used "const" in some prototypes rather than NCURSES_CONST where
+ X/Open Curses was updated to do this, e.g., wscanw, newterm, the
+ terminfo interface. Also use "const" for consistency in the
+ termcap interface, which was withdrawn by X/Open Curses in Issue 5
+ (2007). As of Issue 7, X/Open Curses still lacks "const" for
+ certain return values, e.g., keyname.
+ * modified wbkgd and wbkgrnd to improve compatibility with SVr4
+ curses, changing the way the window rendition is updated when the
+ background character is modified
+ * improved terminfo write/read by modifying the fourth item of the
+ extended header to denote the number of valid strings in the
+ extended string table (see term(5)).
+ * modified the initialization checks for mouse so that the
+ xterm+sm+1006 block will work with terminal descriptions not
+ mentioning xterm.
+
+ These were done to limit or ultimately deprecate features:
+ * deprecated safe-sprintf, since the vsnprintf function, which does
+ what was needed, was standardized long ago.
+ * marked vwprintw and vwscanw as deprecated; recommend using
+ vw_printw and vw_scanw, respectively.
+ * added deprecation warnings for internal functions called by older
+ versions of tack.
+ * removed unused _nc_import_termtype2 function.
+
+ These are improvements to existing features:
+ * check parameter of set_escdelay, return ERR if negative.
+ * check parameter of set_tabsize, return ERR if not greater than
+ zero
+ * correct a status-check in _nc_read_tic_entry() so that if reading
+ a hex/b64 $TERMINFO, and the $TERM does not match, fall-through to
+ the compiled-in search list.
+ * amend check for repeat_char to handle a case where setlocale() was
+ called after initscr
+ * move macro for is_linetouched inside NCURSES_NOMACROS ifndef.
+ * use _nc_copy_termtype2 rather than direct assignment in setupterm,
+ in case it is called repeatedly using fallback terminfo
+ descriptions
+ * improve workaround for Solaris wcwidth versus line-drawing
+ characters
+ * add checks in repair_subwindows to keep the current position and
+ scroll-margins inside the resized subwindow.
+ * correct a buffer-limit in write_entry.c for systems that use
+ caseless filenames.
+ * improved build-time utility report_offsets:
+ + add categories, e.g., "w" for wide-character, "t" for threads
+ to make the report more readable. Reorganized the structures
+ reported to make the categories more apparent.
+ + add NCURSES_GLOBALS and NCURSES_PRESCREEN to report to show
+ how similar the different libtinfo configurations are.
+ * modified some header files to ensure that those include necessary
+ files except for the previously-documented cases
+ * added some traces in initialization to show whether a fallback
+ entry is used.
+ * made minor optimization to reduce calls to _nc_reserve_pairs
+
+ These are corrections to existing features:
+ * fix a special case in PutAttrChar where a cell is marked as
+ alternate-character set, but the terminal does not actually
+ support the given graphic character. This would happen in an older
+ terminal such as vt52, which lacks most line-drawing capability.
+ * corrected flag for "seq" method of db 1.8.5 interface, needed by
+ toe on some of the BSDs.
+ * modify comparison in make_hash.c to correct a special case in
+ collision handling for Caps-hpux11
+ * add extended_slk_color{,_sp} symbols to the appropriate
+ package/*.{map,sym} files
+ * modify lib_setup to avoid calling pthread_self() without first
+ verifying that the address is valid, i.e., for weak symbols
+ * add a couple of broken-linker symbols to the list of versioned
+ symbols to help with link-time optimization versus weak symbols.
+
+ Program improvements
+
+ Several improvements were made to the utility programs:
+
+ clear
+
+ + improved logic for clearing with the E3 extension, in case
+ the terminal scrolls content onto its saved-lines before
+ actually clearing the display, by clearing the saved-lines
+ after clearing the display
+
+ infocmp
+
+ + omit filtering of "OTxx" names which are used for obsolete
+ capabilities, when the output is sorted by long-names. This
+ change helps when making a table of the short/long capability
+ names.
+
+ tic
+
+ + added check for consistent alternate character set
+ capabilities.
+ + added check for paired indn/rin.
+ + added check for terminals with parm_dch vs parm_ich.
+ + added check for the case where setf/setb are given using
+ different strings, but provide identical results to
+ setaf/setab.
+ + corrected check for ich1.
+ + changed a too-large terminal entry from a fatal error to a
+ warning.
+
+ toe
+
+ + ignores any hex/b64 $TERMINFO value in the list of terminfo
+ databases.
+
+ tset
+
+ + replace check in reset command for obsolete "pt" capability
+ using tbc and hts capabilities as clues
+ + modify reset to allow for tabstops at intervals other than 8.
+ + change reset's behavior for margins to simply clear
+ soft-margins if possible, rather than clearing and then
+ setting them according to the terminal's width.
+
+ tput
+
+ + add "x" to getopt string so that "tput -x clear" works.
+
+ Several changes were made to the generated ncurses*config scripts and
+ the analogous ".pc" files to reduce differences between the
+ configurations they report:
+ * modified the ncurse*-config and pc-files to more closely match for
+ the -I and -l options.
+ * filtered out linker-specs from the --libs report.
+ * amended the ncurses*-config and pc-files to take into account the
+ rpath hack which differed between those files.
+ * modified generated ncurses*config and ncurses.pc, ncursesw.pc,
+ etc., to list helper libraries such as gpm for static linking.
+
+ Examples
+
+ Along with the library and utilities, improvements were made to the
+ ncurses-examples. Most of this activity aimed at improving the
+ test-packages. A few changes are more generally useful, e.g., for the
+ main ncurses test-program, and for analyzing traces using the
+ tracemunch script:
+ * improve recovery from error when reading command-character in
+ test/ncurses.c, showing the relevant error message and not exiting
+ on EINTR.
+ * improve tracemunch, by keeping track of TERMINAL* values, and if
+ tracing was first turned on after initialization, attempt to show
+ distinct screen, window and terminal names anyway.
+ * modify tracemunch to accept filename parameters in addition to use
+ as a pipe/filter.
+ * update tracemunch to work with perl 5.26.2, which changed the
+ rules for escaping regular expressions.
+ * add some checks in tracemunch for undefined variables.
+ * modify TurnOn/TurnOff macros (in lib_vidattr.c and lib_vid_attr.c)
+ to avoid expansion of "CUR" in trace.
+
+ There are other new demo/test programs and reusable examples:
+
+ color_content
+ Demonstrate the color_content and extended_color_content
+ functions.
+
+ demo_tabs
+ A simple demo of tabs in curses.
+
+ dump_window
+ A portable curses screen-dump, used to compare ncurses screen
+ contents with Solaris.
+
+ pair_content
+ Demonstrate the pair_content and extended_pair_content
+ functions.
+
+ report_hashing
+ Check hash-tables used for terminfo and termcap names.
+
+ parse_rgb
+ Sample implementation of the ncurses RGB extension from
+ user_caps.5, used in picsmap and savescreen programs.
+
+ A variety of improvements were made to existing programs, both new
+ features as well as options added to make the set of programs more
+ consistent.
+ * add "-l" option to test/background, to dump screen contents in a
+ form that lets different curses implementations be compared.
+ * add "@" command to test/ncurses F-test, to allow rapid jump to
+ different character pages.
+ * added enum, regex examples to test/demo_forms
+ * amend Scaled256() macro in test/picsmap.c to cover the full range
+ 0..1000
+ * corrected pathname used in Ada95 sample programs for explain.txt,
+ to work with test-packages, and used an awk script to split the
+ resulting pathname when it would be too long for a single line.
+ * ignore interrupted system-call in test/ncurses's command-line,
+ e.g., if the terminal were resized.
+ * improved ifdef's for TABSIZE variable, to help with AIX/HPUX
+ ports.
+
+ Terminal database
+
+ There are several new terminal descriptions:
+
+ alacritty, domterm, kitty, mintty, mintty-direct, ms-terminal,
+ n7900, nsterm-build309, nsterm-direct, screen5, ti703, ti707,
+ ti703-w, ti707-w vscode, vscode-direct, xterm-mono, xterm.js
+
+ There are many changes to existing terminal descriptions. Some were
+ updates to several descriptions:
+ * use ansi+rep in a dozen places
+ * add rs1 to konsole, mlterm
+ * improve several flash capabilities with trailing mandatory delays
+ * drop ich1 from rxvt-basic, Eterm and mlterm to improve
+ compatibility with old non-curses programs
+ * add/use xterm+keypad in xterm-new
+ * use xterm+sl-twm for consistency, nine places
+ * improve xm example in xterm+x11mouse and xterm+sm_1006.
+
+ while others affected specific descriptions. These were retested, to
+ take into account changes by their developers:
+
+ terminator, st
+
+ while these are specific fixes based on reviewing documentation, user
+ reports, or warnings from tic:
+
+ adds200:
+
+ + fix typo
+
+ gnome-256color
+
+ + base entry on "gnome", not "vte", for consistency
+
+ interix
+
+ + trim unnecessary setf/setb
+
+ linux-16color
+
+ + accommodate Linux console driver incompatibility introduced
+ in early 2018
+
+ nsterm-256color:
+
+ + add nsterm-build309 to replace nsterm-256color, assigning the
+ latter as an alias of nsterm, to make mouse work with
+ nsterm-256color
+
+ regent40:
+
+ + renumber function-keys to match manual
+
+ regent60:
+
+ + add cd (clr_eos)
+ + corrected acsc
+ + add shifted function-keys
+
+ tvi950:
+
+ + added function-key definitions to agree with Televideo 950
+ manual
+ + corrected acsc
+ + remove bogus kf0
+ + add bel
+
+ tvi955:
+
+ + fix typo
+
+ vi200:
+
+ + add acsc string, including right/down-arrow
+
+ wy50:
+
+ + corrected acsc
+
+ wy50 and wy60:
+
+ + add shifted function-keys as kF1 to kF16
+
+ xterm+x11hilite:
+
+ + eliminate unused p5 parameter.
+
+ A few entries use extensions (user-defined terminal capabilities):
+ * use xterm+sm+1006 (aka "SGR 1006 mouse") for konsole-base and
+ putty
+ * add Smol/Rmol user-defined capability to tmux and vte-2018
+ * add Smulx user-defined capability to tmux, vte-2018
+
+ Documentation
+
+ As usual, this release
+ * improves documentation by describing new features,
+ * attempts to improve the description of features which users have
+ found confusing
+ * fills in overlooked descriptions of features which were described
+ in the NEWS file but treated sketchily in manual pages.
+
+ In addition to providing background information to explain these
+ features and show how they evolved, there are corrections,
+ clarifications, etc.:
+ * Corrections:
+ + correct error-returns listed in manual pages for a few form
+ functions
+ + corrected prototypes in several manpages using script to
+ extract those in compilable form.
+ + fix typo in term.5, improve explanation of format
+ * Clarify in manual pages that vwprintw and vwscanw are obsolete.
+ They have not been part of X/Open Curses since 2007.
+ * New/improved history and portability sections:
+ + curs_addch.3x gives some background for ACS symbols.
+ + curs_getcchar.3x explains a difference between ncurses and
+ X/Open Curses.
+ + curs_getstr.3x gives historical/portability background for
+ the length parameter of wgetnstr.
+ + curs_slk.3x lists a few differences between SVr4 curses and
+ X/Open Curses for soft-keys.
+ + curs_terminfo.3x explains that the initial implementation of
+ terminfo in SVr2 was mostly replaced by other developers in
+ SVr3.
+ + infocmp.1 explains that the initial version of terminfo had
+ no tool for decompiling descriptions. That came later, with
+ SVr3, with a different developer.
+ + tabs.1 tells more than you wanted to know about the tool.
+ + tic.1 explains that the initial version of terminfo had a
+ rudimentary tool (based on termcap) for compiling entries.
+ The tool used with Unix was developed by others for SVr3.
+ + toe.1 explains the origin of this tool.
+ * Improvements for user_caps.5:
+ + mention meml, memu and box1
+ + expanded description of XM
+ + add a clarification regarding the RGB capability.
+ + mention user_caps.5 in the tic and infocmp manual pages.
+ * Other improvements:
+ + curs_add_wch.3x adds note about Unicode terminology for the
+ line-drawing characters.
+ + curs_color.3x improves discussion of error returns and
+ extensions.
+ + curs_mouse.3x explains how the kmous and XM capabilities are
+ used for xterm-mouse input.
+ + curs_refresh.3x improves documentation regarding the virtual
+ and physical screens.
+ + curs_util.3x mentions a difference between SVr4 and X/Open
+ Curses for unctrl.h
+ + curs_variables.3x improves description of the init_tabs
+ capability and TABSIZE variable.
+ + ncurses.3x improves documentation regarding feature-test
+ macros in curses.h
+ + resizeterm.3x about top-level windows which touch the
+ screen's borders.
+ + tput.1 clarifies how tput determines the terminal size.
+
+ There are no new manual pages (all of the manual page updates are to
+ existing pages).
+
+ Some of the improvements are more subtle, relating to the way the
+ information is presented. For instance, the generated terminfo.5 file
+ uses a different table layout, allowing it to use space on wide
+ terminals more effectively.
+
+ Interesting bug-fixes
+
+ While there were many bugs fixed during development of ncurses 6.2,
+ only a few (the reason for this release) were both important and
+ interesting. Most of the bug-fixes were for local issues which did not
+ affect compatibility across releases. Since those are detailed in the
+ NEWS file no elaboration is needed here.
+
+ The interesting bugs were in tic/infocmp's handling of user-defined
+ capabilities. These were not recent bugs. Initially it was a simple
+ problem:
+ * The user-defined capabilities can be any type (boolean, number or
+ string), but once given a type all uses of the name must conform
+ to that type--unless some special support for a particular
+ multi-typed name is built into ncurses.
+ * One of simpleterm's contributors copied some definitions for using
+ tmux's user-defined capabilities in late in 2016.
+
+diff --git a/st.info b/st.info
+@@ -185,7 +185,10 @@ st| simpleterm,
+ tsl=\E]0;,
+ xenl,
+ vpa=\E[%i%p1%dd,
+-
++# Tmux unofficial extensions, see TERMINFO EXTENSIONS in tmux(1)
++ Se,
++ Ss,
++ Tc,
+
+ st-256color| simpleterm with 256 colors,
+ use=st,
+
+ * Later, in (referring to a version from mid-2017), a user asked to
+ have it updated in ncurses.
+ * However, it had an error from the change in late 2016. The
+ terminal description made what tmux expected to be string actually
+ a boolean.
+ Over the years, there were problems with each of simpleterm's
+ terminal descriptions. I repaired those, and usually dealt with
+ the problem.
+ * The difference in this case was that when compiling the terminal
+ database, tic may have in memory the definitions for more than one
+ terminal description (so that it can resolve "use=" clauses).
+ Seeing two different types for the same name, in certain
+ situations it would incorrectly merge the symbol tables for the
+ two terminal descriptions.
+ * On simpleterm's side, their bug was finally fixed in late 2019,
+ three years after the bug was created.
+
+ For ncurses, the elapsed time to fix this bug was less than three
+ years. Someone reported a problem with the terminal description a few
+ weeks after releasing ncurses 6.1 (in tmux #1264), and the terminal
+ description was updated that week (ncurses patch 20180224):
+
+20180224
+ + modify _nc_resolve_uses2() to detect incompatible types when merging
+ a "use=" clause of extended capabilities. The problem was seen in a
+ defective terminfo integrated from simpleterm sources in 20171111,
+ compounded by repair in 20180121.
+ + correct Ss/Ms interchange in st-0.7 entry (tmux #1264) -TD
+
+ The larger part of that change added a check to prevent a simple merge
+ of terminal descriptions where the same user-defined name was used
+ with different types. But it raised some questions:
+ * Was there a reliable way to manage terminal descriptions which
+ used the same extended name in different ways?
+ * Should ncurses provide a registry of well-known extended names,
+ with their types?
+
+ Since the correction to terminfo.src could have been readily adopted
+ by packagers, there was nothing more to be done from ncurses'
+ standpoint on that part. But improving ncurses to prevent issues like
+ that is the reason for making a release.
+
+ Nothing more (constructive) was mentioned with regard to simpleterm.
+ But a few problems were found in the handling of user-defined
+ capabilities:
+ * Forward-references to user-defined capabilities in a "use=" clause
+ did not allocate new data for each use. In tic, successive
+ compilation of terminal entries could add user-defined
+ capabilities to the wrong terminal entry.
+ This was not noticed before, since xterm's terminal descriptions
+ were the main users of the feature, and almost all of the uses of
+ the building-blocks which contained user-defined capabilities were
+ backward-references.
+ * There is one (documented) case where ncurses 6.1 supports a
+ user-defined capability that could be any type (i.e., "RGB"). The
+ check added in February 2018 to guard against mismatches did not
+ handle all of the combinations needed.
+
+ Both of these issues dated from the original implementation of
+ user-defined capabilities. Fixing them does not change the terminal
+ database, but a older tic without the fixes will not be able to handle
+ terminfo sources which rely upon those fixes. Starting in June 2019,
+ the download link for the terminfo source file was capped at that
+ date. The development sources have an up-to-date copy of the file, for
+ people with a legitimate need for it.
+
+ The "-c" (check) option of tic is not very useful if it cannot offer
+ advice on parameters needed for user-defined capabilities. The various
+ Caps files were reorganized to reduce redundancy, and in the common
+ portion (Caps-ncurses), a registry of user-defined capabilities is
+ provided for use by tic. While users can still define their own custom
+ capabilities, tic will not offer any advice when their parameters do
+ not match.
+
+ In ncurses 6.2, tic makes a special check to allow any type for RGB,
+ but its being able to do this relies upon fixes made in the ncurses
+ library in mid-2019.
+
+ Configuration changes
+
+ Major changes
+
+ There are no major changes. Several new options were added to ease
+ integration of packages with systems using different versions of GNAT
+ and ncurses. Also, improvements were made to configure checks.
+
+ Configuration options
+
+ There are a few new/modified configure options:
+
+ --with-config-suffix
+ helps work around a filename conflict with Debian packages
+ versus test-packages.
+
+ --with-ada-libname
+ allows one to rename the "AdaCurses" library (at least one
+ packager prefers a lowercase name).
+
+ --with-fallbacks
+ now ensures there is a value, and adds the fallback information
+ to top-level Makefile summary.
+
+ --with-pcre2
+ check for pcre-posix library to help with MinGW port.
+
+ --with-tic-path and
+
+ --with-infocmp-path
+ help work around problems building fallback source using
+ pre-6.0 tic/infocmp.
+
+ --with-versioned-syms
+ option value can now be a relative pathname.
+
+ Portability
+
+ Many of the portability changes are implemented via the configure
+ script:
+ * ignore $TERMINFO as a default value in configure script if it came
+ from the infocmp -Q option.
+ * distinguish gcc from icc and clang when the --enable-warnings
+ option is not used, to avoid unnecessary warnings about
+ unrecognized inline options
+ * consistently prepend new libraries as they are found during
+ configuration, rather than relying upon the linker to resolve
+ order dependencies of libraries.
+ * modified configure scripts to reduce relinking/ranlib during
+ library install :
+ + use "install -p" when available, to avoid need for ranlib of
+ static libraries.
+ + scripts which use "--disable-relink;" add a 1-second sleep to
+ work around tools which use whole-second timestamps, e.g., in
+ utime rather than the actual file system resolution.
+ * add configure check for getenv to work around implementation shown
+ in Emscripten which overwrites the previous return value on each
+ call.
+ Use that to optionally suppress START_TRACE macro, whose call to
+ getenv may not work properly
+ * change target configure level for _XOPEN_SOURCE to 600 to address
+ use of vsscanf and setenv.
+ * reduce use of _GNU_SOURCE for current glibc where _DEFAULT_SOURCE
+ combines with _XOPEN_SOURCE
+ Allow for Cygwin's newlib when checking for the _DEFAULT_SOURCE
+ symbol.
+ MidnightBSD is now checked for the _XOPEN_SOURCE-related
+ definitions.
+ * If the check for va_copy or __va_copy fails,
+ + configure now tries copying the pointers for va_list, or as
+ an array.
+ + alternatively, it checks for __builtin_va_copy(), which could
+ be used with AIX xlc in c89 mode.
+ * several changes to support a port to Ultrix 3.1:
+ + check if "b" binary feature of fopen works
+ + check for missing feature of locale.h
+ + add fallback for strstr() in test-programs
+ + add fallback for STDOUT_FILENO in test-programs
+ * The test/configure script (used for ncurses-examples) is improved:
+ + work around non-ncurses termcap.h file, e.g., in Slackware.
+ + check for TABSIZE variable.
+ + checks for the X11/Intrinsic.h header, accommodate recent
+ MacOS changes which largely emptied /usr/include.
+
+ Here are some of the other portability fixes:
+ * added dummy "check" rule in top-level and test-Makefile to
+ simplify building test-packages for ArchLinux.
+ * dropped library-dependency on psapi for MinGW port, since
+ win_driver.c defines PSAPI_VERSION to 2, making it use
+ GetProcessImageFileName from kernel32.dll
+ * made build-fixes for configuration using --program-suffix with
+ Ada95, noticed with MacOS but applicable to other platforms
+ without libpanelw, etc.
+ * modified ncurses/Makefile.in to fix a case where Debian/testing
+ changes to the ld --as-needed configuration broke ncurses-examples
+ test packages.
+ * used _WIN32/_WIN64 in preference to __MINGW32__/__MINGW64__
+ symbols to simplify building with Microsoft Visual C++, since the
+ former are defined in both compiler configurations.
+ _________________________________________________________________
+
+Features of ncurses
+
+ The ncurses package is fully upward-compatible with SVr4 (System V
+ Release 4) curses:
+ * All of the SVr4 calls have been implemented (and are documented).
+ * ncurses supports all of the for SVr4 curses features including
+ keyboard mapping, color, forms-drawing with ACS characters, and
+ automatic recognition of keypad and function keys.
+ * ncurses provides these SVr4 add-on libraries (not part of X/Open
+ Curses):
+ + the panels library, supporting a stack of windows with
+ backing store.
+ + the menus library, supporting a uniform but flexible
+ interface for menu programming.
+ + the form library, supporting data collection through
+ on-screen forms.
+ * ncurses's terminal database is fully compatible with that used by
+ SVr4 curses.
+ + ncurses supports user-defined capabilities which it can see,
+ but which are hidden from SVr4 curses applications using the
+ same terminal database.
+ + It can be optionally configured to match the format used in
+ related systems such as AIX and Tru64.
+ + Alternatively, ncurses can be configured to use hashed
+ databases rather than the directory of files used by SVr4
+ curses.
+ * The ncurses utilities have options to allow you to filter terminfo
+ entries for use with less capable curses/terminfo versions such as
+ the HP/UX and AIX ports.
The ncurses package also has many useful extensions over SVr4:
* The API is 8-bit clean and base-level conformant with the X/OPEN
curses specification, XSI curses (that is, it implements all BASE
- level features, but not all EXTENDED features). Most
- EXTENDED-level features not directly concerned with wide-character
- support are implemented, including many function calls not
- supported under SVr4 curses (but portability of all calls is
- documented so you can use the SVr4 subset only).
+ level features, and most EXTENDED features). It includes many
+ function calls not supported under SVr4 curses (but portability of
+ all calls is documented so you can use the SVr4 subset only).
* Unlike SVr3 curses, ncurses can write to the rightmost-bottommost
corner of the screen if your terminal has an insert-character
capability.
* Ada95 and C++ bindings.
- * Support for mouse event reporting with X Window xterm and OS/2
- console windows.
+ * Support for mouse event reporting with X Window xterm and FreeBSD
+ and OS/2 console windows.
* Extended mouse support via Alessandro Rubini's gpm package.
- * The function wresize() allows you to resize windows, preserving
+ * The function wresize allows you to resize windows, preserving
their data.
- * The function use_default_colors() allows you to use the terminal's
+ * The function use_default_colors allows you to use the terminal's
default colors for the default color pair, achieving the effect of
transparent colors.
- * The functions keyok() and define_key() allow you to better control
- the use of function keys, e.g., disabling the ncurses KEY_MOUSE,
- or by defining more than one control sequence to map to a given
- key code.
- * Support for 16-color terminals, such as aixterm and XFree86 xterm.
+ * The functions keyok and define_key allow you to better control the
+ use of function keys, e.g., disabling the ncurses KEY_MOUSE, or by
+ defining more than one control sequence to map to a given key
+ code.
+ * Support for 256-color terminals, such as modern xterm.
+ * Support for 16-color terminals, such as aixterm and modern xterm.
* Better cursor-movement optimization. The package now features a
cursor-local-movement computation more efficient than either BSD's
or System V's.
incorporates a novel, simple, and cheap algorithm that enables it
to make optimal use of hardware scrolling, line-insertion, and
line-deletion for screen-line movements. This algorithm is more
- powerful than the 4.4BSD curses quickch() routine.
+ powerful than the 4.4BSD curses quickch routine.
* Real support for terminals with the magic-cookie glitch. The
screen-update code will refrain from drawing a highlight if the
magic- cookie unattributed spaces required just before the
types even when no terminfo tree or termcap file is accessible
(this may be useful for support of screen-oriented programs that
must run in single-user mode).
- * The tic(1)/captoinfo utility provided with ncurses has the ability
- to translate many termcaps from the XENIX, IBM and AT&T extension
+ * The tic/captoinfo utility provided with ncurses has the ability to
+ translate many termcaps from the XENIX, IBM and AT&T extension
sets.
- * A BSD-like tset(1) utility is provided.
+ * A BSD-like tset utility is provided.
* The ncurses library and utilities will automatically read terminfo
entries from $HOME/.terminfo if it exists, and compile to that
directory if it exists and the user has no write access to the
other entries in the same source file (as in System V) but also to
compiled entries in either the system terminfo directory or the
user's $HOME/.terminfo directory.
- * A script (capconvert) is provided to help BSD users transition
- from termcap to terminfo. It gathers the information in a TERMCAP
- environment variable and/or a ~/.termcap local entries file and
- converts it to an equivalent local terminfo tree under
- $HOME/.terminfo.
- * Automatic fallback to the /etc/termcap file can be compiled in
- when it is not possible to build a terminfo tree. This feature is
- neither fast nor cheap, you don't want to use it unless you have
- to, but it's there.
* The table-of-entries utility toe makes it easy for users to see
exactly what terminal types are available on the system.
* The library meets the XSI requirement that every macro entry point
have a corresponding function which may be linked (and will be
prototype-checked) if the macro definition is disabled with
#undef.
- * An HTML "Introduction to Programming with NCURSES" document
- provides a narrative introduction to the curses programming
- interface.
+ * Extensive documentation is provided (see the Additional Reading
+ section of the ncurses FAQ for online documentation).
+
+Applications using ncurses
- State of the Package
+ The ncurses distribution includes a selection of test programs
+ (including a few games). These are available separately as
+ ncurses-examples
- Numerous bugs present in earlier versions have been fixed; the library
- is far more reliable than it used to be. Bounds checking in many
- `dangerous' entry points has been improved. The code is now type-safe
- according to gcc -Wall. The library has been checked for malloc leaks
- and arena corruption by the Purify memory-allocation tester.
+ The ncurses library has been tested with a wide variety of
+ applications including:
- The ncurses code has been tested with a wide variety of applications
- including (versions starting with those noted):
+ aptitude
+ FrontEnd to Apt, the debian package manager
+
+ https://wiki.debian.org/Aptitude
cdk
Curses Development Kit
- [3]http://invisible-island.net/cdk/
- [4]http://www.vexus.ca/products/CDK/
+
+ https://invisible-island.net/cdk/
ded
directory-editor
- [5]http://invisible-island.net/ded/
+
+ https://invisible-island.net/ded/
dialog
the underlying application used in Slackware's setup, and the
- basis for similar applications on GNU/Linux.
- [6]http://invisible-island.net/dialog/
+ basis for similar install/configure applications on many
+ systems.
+
+ https://invisible-island.net/dialog/
lynx
- the character-screen WWW browser
- [7]http://lynx.isc.org/release/
+ the text WWW browser
- Midnight Commander
- file manager
- [8]http://www.ibiblio.org/mc/
+ https://lynx.invisible-island.net/
mutt
mail utility
- [9]http://www.mutt.org/
+
+ http://www.mutt.org/
ncftp
file-transfer utility
- [10]http://www.ncftp.com/
+
+ https://www.ncftp.com/
nvi
- New vi versions 1.50 are able to use ncurses versions 1.9.7 and
- later.
- [11]http://www.bostic.com/vi/
+ New vi uses ncurses.
- pinfo
- Lynx-like info browser.
- [12]http://dione.ids.pl/~pborys/software/pinfo/
+ https://sites.google.com/a/bostic.com/keithbostic/vi
+
+ ranger
+ A console file manager with VI key bindings in Python.
+
+ https://ranger.github.io/
tin
- newsreader, supporting color, MIME [13]http://www.tin.org/
+ newsreader, supporting color, MIME
+
+ http://www.tin.org/
- vh-1.6
- Volks-Hypertext browser for the Jargon File
- [14]http://www.debian.org/Packages/unstable/text/vh.html
+ vifm
+ File manager with vi like keybindings
+
+ https://vifm.info/
as well as some that use ncurses for the terminfo support alone:
minicom
- terminal emulator
- [15]http://www.netsonic.fi/~walker/minicom.html
+ terminal emulator for serial modem connections
+
+ https://alioth.debian.org/projects/minicom/
+
+ mosh
+ a replacement for ssh.
+
+ https://mosh.mit.edu/
+
+ tack
+ terminfo action checker
+
+ https://invisible-island.net/ncurses/tack.html
+
+ tmux
+ terminal multiplexor
+
+ https://github.com/tmux/tmux/wiki
vile
- vi-like-emacs
- [16]http://invisible-island.net/vile/
+ vi-like-emacs may be built to use the terminfo, termcap or
+ curses interfaces.
- The ncurses distribution includes a selection of test programs
- (including a few games).
+ https://invisible-island.net/vile/
+
+ and finally, those which use only the termcap interface:
+
+ emacs
+ text editor
+
+ https://www.gnu.org/software/emacs/
+
+ less
+ The most commonly used pager (a program that displays text
+ files).
+
+ http://www.greenwoodsoftware.com/less/
+
+ screen
+ terminal multiplexor
+
+ https://www.gnu.org/software/screen/
-Who's Who and What's What
+ vim
+ text editor
- Zeyd Ben-Halim started it from a previous package pcurses, written by
- Pavel Curtis. Eric S. Raymond continued development. Jürgen Pfeifer
- wrote most of the form and menu libraries. Ongoing work is being done
- by [17]Thomas Dickey. Thomas Dickey acts as the maintainer for the
- Free Software Foundation, which holds the copyright on ncurses.
- Contact the current maintainers at [18]bug-ncurses@gnu.org.
+ https://www.vim.org/
- To join the ncurses mailing list, please write email to
- bug-ncurses-request@gnu.org containing the line:
- subscribe <name>@<host.domain>
+Development activities
+
+ Zeyd Ben-Halim started ncurses from a previous package pcurses,
+ written by Pavel Curtis. Eric S. Raymond continued development.
+ Juergen Pfeifer wrote most of the form and menu libraries.
+
+ Ongoing development work is done by Thomas E. Dickey. Thomas E. Dickey
+ has acted as the maintainer for the Free Software Foundation, which
+ holds a copyright on ncurses for releases 4.2 through 6.1. Following
+ the release of ncurses 6.1, effective as of release 6.2, copyright for
+ ncurses reverted to Thomas E. Dickey (see the ncurses FAQ for
+ additional information).
+
+ Contact the current maintainers at
+
+ bug-ncurses@gnu.org
+
+ To join the ncurses mailing list, please write email to
+
+ bug-ncurses-request@gnu.org
+
+ containing the line:
+
+ subscribe <name>@<host.domain>
This list is open to anyone interested in helping with the development
and testing of this package.
- Beta versions of ncurses and patches to the current release are made
- available at [19]ftp://invisible-island.net/ncurses/ .
+ Beta versions of ncurses are made available at
+
+ ftp://ftp.invisible-island.net/ncurses/current/ and
+ https://invisible-mirror.net/archives/ncurses/current/ .
+
+ Patches to the current release are made available at
+
+ ftp://ftp.invisible-island.net/ncurses/6.1/ and
+ https://invisible-mirror.net/archives/ncurses/6.1/ .
+
+ There is an archive of the mailing list here:
-Future Plans
+ http://lists.gnu.org/archive/html/bug-ncurses (also https)
- * Extended-level XPG4 conformance, with internationalization
- support.
- * Ports to more systems, including DOS and Windows.
+Related resources
- We need people to help with these projects. If you are interested in
- working on them, please join the ncurses list.
+ The release notes make scattered references to these pages, which may
+ be interesting by themselves:
+ * ncurses licensing
+ * Symbol versioning in ncurses
+ * Comments on ncurses versus slang (S-Lang)
+ * tack - terminfo action checker
+ * tctest - termcap library checker
+ * Terminal Database
-Other Related Resources
+Other resources
The distribution provides a newer version of the terminfo-format
- terminal description file maintained by [20]Eric Raymond . Unlike the
+ terminal description file once maintained by Eric Raymond . Unlike the
older version, the termcap and terminfo data are provided in the same
- file.
+ file, which also provides several user-definable extensions beyond the
+ X/Open specification.
You can find lots of information on terminal-related topics not
- covered in the terminfo file at [21]Richard Shuford's archive .
-
-References
-
- 1. ftp://ftp.gnu.org/gnu/ncurses/
- 2. ftp://invisible-island.net/ncurses/
- 3. http://invisible-island.net/cdk/
- 4. http://www.vexus.ca/products/CDK/
- 5. http://invisible-island.net/ded/
- 6. http://invisible-island.net/dialog/
- 7. http://lynx.isc.org/release/
- 8. http://www.ibiblio.org/mc/
- 9. http://www.mutt.org/
- 10. http://www.ncftp.com/
- 11. http://www.bostic.com/vi/
- 12. http://dione.ids.pl/~pborys/software/pinfo/
- 13. http://www.tin.org/
- 14. http://www.debian.org/Packages/unstable/text/vh.html
- 15. http://www.netsonic.fi/~walker/minicom.html
- 16. http://invisible-island.net/vile/
- 17. mailto:dickey@invisible-island.net
- 18. mailto:bug-ncurses@gnu.org
- 19. ftp://invisible-island.net/ncurses/
- 20. http://www.catb.org/~esr/terminfo/
- 21. http://www.cs.utk.edu/~shuford/terminal_index.html
+ covered in the terminfo file at Richard Shuford's archive . The
+ collection of computer manuals at bitsavers.org has also been useful.
+
+ * Overview
+ * Release Notes
+ + Library improvements
+ o New features
+ o Other improvements
+ + Program improvements
+ o Utilities
+ o Examples
+ + Terminal database
+ + Documentation
+ + Interesting bug-fixes
+ + Configuration changes
+ o Major changes
+ o Configuration options
+ + Portability
+ * Features of ncurses
+ * Applications using ncurses
+ * Development activities
+ * Related resources
+ * Other resources