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. + 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 releases such as BSD/OS, FreeBSD and NetBSD to - switch over to ncurses.
+ keepers of unix releases such as + BSD/OS, FreeBSD and NetBSD to switch over to ncurses. + +Since 1995, ncurses has been + ported to many systems:
+ +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!
+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.
+ including + +Full manual pages are provided for the library and tools.
+ +The ncurses distribution is + available at ncurses' homepage:
+ +++ +https://invisible-island.net/archives/ncurses/ + or
+
+ https://invisible-mirror.net/archives/ncurses/ .
It is also available at the GNU distribution site
-The ncurses distribution is available via anonymous FTP at the
- GNU distribution site ftp://ftp.gnu.org/gnu/ncurses/ .
+
+ +- It is also available at ftp://invisible-island.net/ncurses/ . +
These notes are for ncurses + @VERSION@, released April 27, 2024.
-This is a bug-fix release, correcting a small number of urgent - problems in the ncurses library from the 5.8 release.
+This release is designed to be source-compatible with + ncurses 5.0 through 6.4; 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.
-It also improves the Ada95 binding:
+There are, of course, numerous other improvements, listed in + this announcement.
+ +The most important + bug-fixes/improvements dealt with robustness issues. The + release notes also mention some other bug-fixes, but are focused + on new features and improvements to existing features since + ncurses 6.4 release.
+ +These are new features:
Those were a proof of concept. For the 5.9 release, those - scripts are augmented with rpm- and dpkg-scripts used in test - builds against a variety of gnat- and system ncurses versions - as old as gnat 3.15 and ncurses 5.4 (see snapshots and - systems tested here.
-The low-level terminfo and termcap interfaces are used + both by the higher-level curses library, as well as by many + applications.
+ +The functions which convert parameterized terminal
+ capability strings for output to the terminal
+ (tiparm and tparm) analyze the
+ capability string to determine which parameters are strings
+ (i.e., addresses), versus numbers (not addresses).
The library's analysis of a capability string may differ + from the calling application's design if environment + variables are used to point to an invalid terminal database. + This is a longstanding problem with all + implementations of terminfo, dating from the early 1980s.
+ +Two new functions address this problem: by providing a + function which allows the calling application to tell ncurses + how many string-parameters to expect:
+ +tiscan_s helps applications check
+ formatting capabilities that would be passed to
+ tiparm_s.tiparm_s provides applications a way to
+ tell ncurses what the expected parameters are for a
+ capability.The ncurses library supports a compile-time feature
+ (enabled with the configure --enable-check-size
+ option) which simplifies initialization with terminals which
+ do not negotiate window (screen) size. This is done in
+ setupterm, by providing for using ANSI
+ cursor-position report (in user6/user7 terminfo capabilities)
+ to obtain the screen size if neither environment variables or
+ ioctl is used.
The ncurses test-program with options
+ “-E -T” demonstrates this
+ feature.
SCREENThis release drops compatibility with obsolete versions of + tack, e.g., pre-1.08
+ +These are improvements to existing features:
In addition to the new, safer function
+ tiparm_s, ncurses adds checks to make the older
+ tiparm, tparm and
+ tgoto functions safer:
the terminfo functions tiparm and
+ tparm ensure that the capability string
+ comes from the terminal description which ncurses loads,
+ rather than from random data which the application
+ happens to have.
the tgoto function disallows capabilities
+ which its analysis shows will attempt to use string
+ parameters.
ncurses uses internal functions which correspond to
+ tiparm, and tgoto which ensure
+ that the capability strings which are passed to these
+ functions come from the loaded terminal description.
improve check in lib_tparm.c, ensuring that a
+ char* fits into a TPARM_ARG
modify _nc_syserr_abort to use
+ _nc_env_access, rather than only checking root
+ uid
improve thread lock in lib_trace.c
modify flushinp to use file descriptors in
+ SCREEN, rather than from TERMINAL,
+ and check if they are for a terminal, like SVr4
modify mcprint to use file descriptor in
+ SCREEN, for consistency
modify internal function _nc_read_file_entry
+ to show relevant filename in warnings
improve checks in internal function
+ convert_string for corrupt terminfo entry
review/improve handling of out-of-memory conditions
+limit delays to 30 seconds, i.e., padding delays in
+ terminfo, as well as napms and
+ delay_output functions
fix reallocation loop for vsnprintf in
+ _nc_sprintf_string by copying the va_list
+ variable
modify delscreen to limit the windows which
+ it creates to just those associated with the screen
modify endwin to return an error if it is
+ called again without an intervening screen update
modify wenclose to handle pads
eliminate use of PATH_MAX in
+ lib_trace.c
provide for any CCHARW_MAX greater than 1
These are corrections to existing features:
wresize allows you to resize
- windows, preserving their data.use_default_colors allows you to
- use the terminal's default colors for the default color pair,
- achieving the effect of transparent colors.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.--enable-ext-colors
- option.quickch
- routine.#undef.correct loop termination condition in
+ waddnstr and waddnwstr
improve parsing in internal function
+ _nc_msec_cost, allowing a single decimal
+ point
amend parameter check for entire string versus specific
+ length in winsnstr and wins_nwstr
+ to match Solaris; make similar correction to
+ wins_nwstr
correct internal function wadd_wch_literal
+ when adding a non-spacing character to a double-width
+ character
correct definition of Charable macro for
+ non-wide ncurses library .
The ncurses code has been tested with a wide variety of - applications including (versions starting with those noted):
+Several improvements were made to the
+ utility programs. Some were done to make the infocmp
+ option “-u” option help refactor the
+ terminal database.
add limit checks for processing extended capabilities
+ with the “-u” option
correct initial alignment of extended capabilities, so
+ that the “-u” option can be used
+ for more than two terminal types
modify “-u” option to not
+ report cancels for strings which were already cancelled
+ in a use'd chunk.
correct an assignment “-u”
+ for detecting if a boolean is unset in a base entry and
+ set in a use'd chunk, i.e., if it was cancelled.
correct limit-check when dumping tc/use clause via
+ “-I”
check return value of _nc_save_str, in
+ special case where extended capabilities are processed
+ but the terminal description was not initialized
modify check for multiply defined aliases to report + problems within the current runtime rather than for + conflicts with pre-existing terminal descriptions.
+disallow using $TERMINFO or
+ $HOME/.terminfo when
+ “-o” option is used
add “-v” option to tput, to
+ show warnings
modify reset command to avoid altering clocal + if the terminal uses a modem
+modify reset feature to avoid 1-second sleep + if running in a pseudo-terminal
+Along with the library and utilities, improvements were made + to the ncurses-examples:
+ +modify test_tparm to account for extended
+ capabilities
corrected mouse mask in test/testcurs.c
modify test/clip_printw.c to optionally test
+ non-wrapped updates
modify test/test_mouse.c to use curses api
+ for raw/noraw
modify test/clip_printw.c to optionally test
+ non-wrapped updates
There is one new demo/test programs:
-This program shows the return-status from
+ endwin with different combinations of
+ endwin (repeated), initscr,
+ newterm.
There are several new terminal descriptions:
-linux+kbs + for terminals which imitate xterm's behavior with Linux
+rio, + rio-direct
+vt100+noapp, + vt100+noapp+pc, + xterm+app+pc, + xterm+decedit + from xterm + #389
+putty+cursor + to reflect amending of modified cursor-keys in 2021
+There are many changes to existing terminal descriptions. Some
+ were updates to several descriptions, using the
+ infocmp “-u” option in a
+ script to determine which building-block entries could
+ be used to replace multiple capability settings (and trim
+ redundant information).
Other changes include:
+ +document + XF, kxIN and kxOUT
+add note on sun + regarding wscons/cmdtool/shelltool
+remove DECCOLM+DECSCLM from foot
+add xterm+focus to foot+base
+add ecma+strikeout to putty
+use CSI 3J in vte-2017
+use oldxterm+sm+1006 in vte-2014
+modify xgterm + to work around line-drawing bug
+add xterm focus mode 1004 to xterm+focus + as fe/fd capabilities, like vim.
+add xterm+focus to alacritty+common
+add XR/xr, to work with vim, and use RV/rv to denote DA2 + and its response
+add XF flag to xterm+focus + so that termcap applications can be aware of terminals which + may support focus in/out
+use xterm+focus in xterm-p370 + and tmux
+remove xterm+sm+1006 from tmux
+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:
+ +add assignment in CF_MAN_PAGES to fill in
+ value for TERMINFO_DIRS in ncurses, terminfo
+ and tic manpages.
clarify interaction of -R option versus
+ -C, -I and -r in
+ infocmp manpage.
correct manpage description of panel_hidden.
+improve manpage description for addch versus unctrl + format used for non-printable characters.
+improve manpages discussing file descriptors in + low-level functions.
+improve description of search rules for terminal + descriptions in terminfo manpage.
+modify dist.mk to avoid passing developer's comments + in manpages into the generated html documentation.
+modify test-package "ncurses6-doc" to use + manpage-aliases, which in turn required a change to the + configure script to factor in the extra-suffix option + when deriving alias names.
+New/improved history and portability sections:
+ +add information about "ttycap", termcap's forerunner, + to tset.1
+document limitations of tparm, and error-returns in + curs_terminfo.3x
+document limitations of tgoto, and error-returns in + curs_termcap.3x
+Other improvements:
+ +This release has many changes to improve the + formatting and style of the manpages.
+Manpages now use consistent section-naming, page + headers and footers (including the modification date for + each page).
+Table layout has been revised.
+There are no new manual pages (all of the manual page updates + are to existing pages).
+ +The changes to tparm, tgoto which improve + the design of the low-level interfaces are interesting, + but are not bug-fixes per se.
+ +These are the major changes (aside from introducing tiparm_s):
+ +use wide-character (ncursesw) by default
+use opaque typedefs by default
+However, most of the work on configure scripts was done to + reduce warnings within the configure script:
+ +intrusive warnings from GNU grep regarding fgrep and + egrep
+fatal errors in compile-checks, arising from recent + “Modern C” efforts by some developers which + caused longstanding configure checks to fail.
+ +After repairing the configure script, none of that + activity affected ncurses because stricter warnings are used + routinely in development.
+Other improvements made to configure checks include
+ +use string-hacks + in alloc_entry.c, alloc_type.c and hardscroll.c, overlooked + due to compiler changes in recent OpenBSD releases
+revise progs.priv.h to provide for NC_ISATTY reuse
+configure check for MB_LEN_MAX provides warning as + needed
+trim a space after some "-R" options, fixing builds for + applications built using clang and ncurses on Solaris
+work around misconfiguration of MacPorts gcc13, which + exposes invalid definition of MB_LEN_MAX in gcc's + fallback copy of limits.h
+modified experimental Windows driver works with xterm + mouse protocol
+There are a few new configure options:
+ +Compile with environment restriction, so certain + environment variables are not available when running via a + setuid/setgid application. These are (for example + $TERMINFO) those that allow the search path for the + terminfo or termcap entry to be customized.
+ +A setuid/setgid application inherits its environment + variables from the current user, in contrast to sudo which + may limit the environment variables that ncurses uses.
Compile-in feature to detect screensize for terminals + which do not advertise their screensize, e.g., serial + terminals.
+Override the displayed (rather than compiled-in) ABI. Only + packagers who have created configurations where the ABI + differs from ncurses should be interested in this option.
+When stripping executables during install, use the + specified program rather than “strip” overriding + program chosen by the install program for stripping + executables.
+These configure options are modified:
The optional DIR parameter can now be + “auto” to automatically use pkg-config's library + directory.
-The default is $(libdir).
+ -The default is “auto” which tells the + configure script to choose BS or DEL according to platform + defaults.
+The ncurses distribution includes a selection of test programs - (including a few games).
+Many of the portability changes are implemented via the + configure script:
-add/use configure check for clock_gettime, to
+ supersede gettimeofday.
modify configure script check for pkg-config library + directory to take into account an older version 0.15.0 which + used PKG_CONFIG_PATH but not PKG_CONFIG_LIBDIR
+allow for MinGW32-/64-bit configurations to use + _DEFAULT_SOURCE
+modify CF_XOPEN_SOURCE macro's amend default case to avoid + undefining _XOPEN_SOURCE if _POSIX_C_SOURCE is defined
+updated configure script macro CF_XOPEN_SOURCE, for + uClibc-ng
+modify version-check for gcc/g++, now works for msys2
+build-fixes related to configure-options and/or + platform:
+ +other configure-script improvements:
+ +Here are some of the other portability fixes:
+ +modify configure scripts/makefiles to omit + KEY_RESIZE if the corresponding SIGWINCH + feature is disabled
+increase MB_CUR_MAX to 16, matching glibc's + MB_LEN_MAX
+add BSD erase2 to characters handled by + tset/reset
+use getauxval when available, to improve + setuid/setgid checks
+set dwShareMode in calls to + CreateConsoleScreenBuffer
+use CreateFile with "CONIN$", + "CONOUT$" rather than GetStdHandle to + obtain a handle on the actual console, avoiding redirection + in the MinGW/Win32 configurations
+modify MinGW driver to return KEY_BACKSPACE when + an unmodified VK_BACK virtual key is entered
+modify MinGW configuration to provide for running in + MSYS/MSYS2 shells, assuming ConPTY support
+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 the + features of SVr4 curses including keyboard mapping, color, + form drawing with ACS characters, and automatic recognition + of keypad and function keys.
+ncurses provides work-alike + replacements of SVr4 supplemental libraries based on curses, + but which were not specified by X/Open Curses:
+ +the panel library, supporting a stack of windows with + backing store
+the menu 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 that 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, and almost all + 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 + FreeBSD and OS/2 console windows.
+Extended mouse support via Alessandro Rubini's gpm + package.
+The function wresize allows you to resize
+ windows, preserving their data.
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 direct-color terminals, such as modern + xterm.
+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.
+Super hardware scrolling support. The screen-update code
+ 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.
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 beginning and after the end would step on a non-space + character. It will automatically shift highlight boundaries + when doing so would make it possible to draw the highlight + without changing the visual appearance of the screen.
+It is possible to generate the library with a list of + pre-loaded fallback entries linked to it so that it can serve + those terminal 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/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 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 system + directory. This feature makes it easier for users to have + personal terminfo entries without giving up access to the + system terminfo directory.
+You may specify a path of directories to search for + compiled descriptions with the environment variable + TERMINFO_DIRS (this generalizes the feature provided by + TERMINFO under stock System V.)
+In terminfo source files, use capabilities may refer not + just to 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.
+The table-of-entries utility toe makes it easy for users to see + exactly what terminal types are available on the system.
+X/Open Curses permits most functions it specifies to be + made available as macros as well. ncurses does this
+ +stdscr, andExcept for the last case, ncurses provides a non-macro
+ implementation of the function. If the macro definition is
+ disabled with #undef, or by defining
+ NCURSES_NOMACROS the function may be linked (and
+ its calls will be checked against the prototype).
Extensive documentation is provided (see the Additional + Reading section of the ncurses FAQ for online + documentation).
+The ncurses distribution + includes a selection of test programs (including a few games). + These are available separately as ncurses-examples
+ +The ncurses library has been tested with a wide variety of + applications including:
+ +++ ++
+- aptitude +
+ +- +
+ +FrontEnd to Apt, the debian package manager
+ + +- cdk +
+ +- +
+ +Curses Development Kit
+ + +- ded +
+ +- +
+ +directory-editor
+ + +- dialog +
+ +- +
+ +the underlying application used in Slackware's setup, + and the basis for similar install/configure applications on + many systems.
+ + +- lynx +
+ +- +
+ +the text WWW browser
+ + +- mutt +
+ +- +
+ +mail utility
+ + +- ncftp +
+ +- +
+ +file-transfer utility
+ + +- nvi +
+ +- +
+ +New vi uses ncurses.
+ ++ https://sites.google.com/a/bostic.com/keithbostic/the-berkeley-vi-editor-home-page
+
+ +- ranger +
+ +- +
+ +A console file manager with VI key bindings in + Python.
+ + +- tin +
+ +- +
+ +newsreader, supporting color, MIME
+ + +- vifm +
+ +- +
+File manager with vi like keybindings
+ + +
as well as some that use ncurses for the terminfo support alone:
+ +++ ++
+- minicom +
+ +- +
+ +terminal emulator for serial modem connections
+ + +- mosh +
+ +- +
+ +a replacement for
+ + +ssh.- tack +
+ +- +
+ +terminfo action checker
+ + +- tmux +
+ +- +
+ +terminal multiplexor
+ + +- vile +
+ +- +
+vi-like-emacs may be built to use the terminfo, + termcap or curses interfaces.
+ + +
and finally, those which use only the termcap interface:
+ +++ ++
+- emacs +
+ +- +
+ +text editor
+ + +- less +
+ +- +
+ +The most commonly used pager (a program that + displays text files).
+ + +- screen +
+ +- +
+ +terminal multiplexor
+ + +- vim +
+ +- +
+text editor
+ + +
Zeyd Ben-Halim started ncurses + 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 - Thomas Dickey. - Thomas Dickey acts as the maintainer for the Free Software - Foundation, which holds the copyright on ncurses. 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> -+ 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 held 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 ftp://invisible-island.net/ncurses/ .
+Beta versions of ncurses are + made available at
+ +++ +https://invisible-island.net/archives/ncurses/current/ + and
+
+ https://invisible-mirror.net/archives/ncurses/current/ .
Patches to the current release are made available at
+ ++https://invisible-island.net/archives/ncurses/6.4/ + and
+
+ https://invisible-mirror.net/archives/ncurses/6.4/ .
There is an archive of the mailing list here:
-http://lists.gnu.org/archive/html/bug-ncurses - (also https)
++ ++ +
The release notes make scattered references to these pages, + which may be interesting by themselves:
The distribution provides a newer version of the + terminfo-format terminal description file once maintained by + Eric Raymond . Unlike the older version, the termcap and - terminfo data are provided in the same file, and provides several - user-definable extensions beyond the X/Open specification. + terminfo data are provided in the same file, which also provides + several user-definable extensions beyond the X/Open Curses + specification.
You can find lots of information on terminal-related topics - not covered in the terminfo file at - Richard Shuford's archive .
+ not covered in the terminfo file in Richard Shuford's + archive (original). + The collection of computer manuals at bitsavers.org has also been + useful. + +