# Announcing ncurses 5.8

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.

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.

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.

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/ .

# Release Notes

This release is designed to be upward compatible from ncurses 5.0 through 5.7; very few applications will require recompilation, depending on the platform. These are the highlights from the change-log since ncurses 5.7 release.

## Interface changes

- turn on `_XOPEN_CURSES` definition in `curses.h`.
- change `_nc_has_mouse` to `has_mouse`, reflect its use in C++ and Ada95.
- add `is_pad` and `is_subwin` functions for opaque access to the WINDOW structure.
- add `tiparm`, based on review of X/Open Curses Issue 7.

## New features and improvements

### Library Improvements

- add a terminal driver for Windows console, which supports a MinGW port to Windows.
- add extended functions which specify the `SCREEN` pointer for several curses functions which use the global `SP`.
- improve the `NCURSES_NO_UTF8_ACS` feature by adding a check for an extended terminfo capability `U8`.
- improve performance of `tigetstr`, etc., by using hashing code from tic.
- add WACS_xxx definitions to wide-character configuration for thick- and double-lines.
- modify init_pair to allow caller to create extra color pairs beyond the color_pairs limit, which use default colors.

### Improvements to Programs

- add `tabs` program.
- modify tic's -I/-C dump to reformat acsc strings into canonical form (sorted, unique mapping).
- add checks in tic for inconsistent cursor-movement controls, and for inconsistent printer-controls.
- add special case to `_nc_infotocap` (used by tic and infocmp) to recognize the `setaf`/`setab` strings from `xterm+256color` and `xterm+88color,` and provide a reduced version which works with termcap.

### Terminal Database

- added entries:
  - `bterm` terminfo entry, based on bogl 0.1.18
  - `cons25-debian` entry
  - `eterm-color` entry
  - `linux-16color`
  - `mlterm+256color` entry, for mlterm 3.0.0
  - several screen-bce.xxx entries
  - `screen.Eterm` terminfo entry
  - `vwmterm` entry
  - `xterm-utf8` entry as a demo of the `U8` feature
- updated/improved entries:
  - use extended capabilities:
    - add `U8` feature to denote entries for terminal emulators which do not support VT100 SI/SO when processing UTF-8 encoding
    - add `XT` capability to entries for terminals that support both xterm-style mouse- and title-controls, for `screen` which special-cases TERM beginning with `xterm` or `rxvt`
  - improvements based on new checks in tic:
  - - fill in no-parameter forms of cursor-movement where a parameterized form is available
    - fill in missing cursor controls where the form of the controls is ANSI
    - add parameterized cursor-controls to linux-basic
    - modify `nsterm,` `xnuppc` and `tek4115` to make `sgr`/`sgr0` consistent
    - change several terminfo entries to make consistent use of ANSI clear-all-tabs
  - extend `ansi.sys` `pfkey` capability from kf1-kf10 to kf1-kf48, moving function key definitions from `emx-base` for consistency.
  - correct missing final 'p' in `pfkey` capability of `ansi.sys-old`.
  - rename `atari` and `st52` terminfo entries to atari-old, st52-old, use newer entries from FreeMiNT.
  - repurpose `gnome` terminfo entries as `vte`, retaining `gnome` variants for compatibility, but generally deprecating those since the VTE library is what actually defines the behavior of "gnome", etc., since 2003.
  - improve `interix` `smso` terminfo capability by using reverse rather than bold.
  - correct `initc` capability of `linux-c-nc` end-of-range, make similar change for `dg+ccc` and `dgunix+ccc`.
  - update `minix` terminfo entry.
  - updated `nsterm*` entries.
  - remove unnecessary `kcan` assignment to `^C` from `putty`.
  - suppress `ncv` in `screen` and `konsole-base` entries, allowing underline.
  - change ncv and op capabilities in `sun-color` terminfo entry to match Sun's entry for this.
  - fix typo in `rmso` for `tek4106` entry.
  - improve `acsc` string for `vt52`, show arrow keys.
  - add hard-reset for `rs2` to `wsvt25` to help ensure that reset ends the alternate character set.
  - add `ccc` and `initc` capabilities to `xterm-16color`.

## Major bug fixes

- ncurses library
  - wide character support
    - modify length returned by `getcchar` to count the trailing null which is documented in X/Open.
    - fix an infinite recursion when adding a legacy-coding 8-bit value using `insch`.
    - improve a workaround in adding wide-characters, when a control character is found. The library uses `unctrl` to obtain a printable version of the control character, but was not passing color or video attributes.
    - modify `waddch_literal`, updating line-pointer after a multicolumn character is found to not fit on the current row, and wrapping is done. Since the line-pointer was not updated, the wrapped multicolumn character was written to the beginning of the current row.
    - fixes in `wins_nwstr` and related functions to ensure that special characters, i.e., control characters are handled properly with the wide-character configuration.
    - correct internal `_nc_insert_ch` to use `_nc_insert_wch` when inserting wide characters, since the `wins_wch` function that it used did not update the cursor position.
  - mouse
    - add check if `Gpm_Open` returns a -2, e.g., for "xterm". This is normally suppressed but can be overridden using `$NCURSES_GPM_TERMS`. Ensure that `Gpm_Close` is called in this case.
    - add check in mouse-driver to disable connection if GPM returns a zero, indicating that the connection is closed.
    - modify `getmouse` to act as its documentation implied, returning on each call the preceding event until none are left. When no more events remain, it will return `ERR`.
  - miscellaneous
    - improve handling of color-pairs embedded in attributes for the extended-colors configuration.
    - add check for failure to open hashed-database needed for db4.6.
    - modify use of `$CC` environment variable which is defined by X/Open as a curses feature, to ignore it if it is not a single character.
    - modify declaration of `cur_term` when broken-linker is used, but enable-reentrant is not, to match pre-5.7.
    - correct limit-checks in `derwin`.
    - remove old check in `mvderwin` which prevented moving a derived window whose origin happened to coincide with its parent's origin.
    - correct limit-checks in `newwin`, to ensure that windows have nonzero size.
    - modify `set_curterm` to make broken-linker configuration work with changes from 20090228.
    - modify `wgetch` to ensure it checks `SIGWINCH` when it gets an error in non-blocking mode.
    - correct limit-check in `wredrawln`, accounting for `begy`/`begx` values.
    - fix a null-pointer check in `_nc_format_slks` in lib_slk.c, from 20070704 changes.
    - correct translation of "^" in `_nc_infotocap`, used to transform terminfo to termcap strings.
    - modify `_nc_wgetch` to check for a -1 in the fifo, e.g., after a `SIGWINCH`, and discard that value, to avoid confusing application.
- other libraries
  - correct transfer of multicolumn characters in multirow `field_buffer`, which stopped at the end of the first row due to filling of unused entries in a cchar_t array with nulls.
  - correct buffer-size after internal resizing of wide-character `set_field_buffer`, broken in 20081018 changes.
  - correct layout of working window used to extract data in wide-character configured by `set_field_buffer`

## Portability

- configure script:
  - new options:
    --disable-libtool-version
      use the "-version-number" feature which was added in libtool 1.5. The default value for the option uses the newer feature, which makes libraries generated using libtool compatible with the standard builds of ncurses.
    --disable-rpath-hack
      disable a feature which adds rpath options for libraries in unusual places.
    --enable-interop
      integrate changes for generic/interop support to form-library.
    --enable-pc-files
      generate ".pc" files for each of the libraries, and install them in `pkg-config`'s library directory.
    --enable-pthreads-eintr
      control whether to allow `EINTR` to interrupt a read operation in `wgetch`. This applies only to the pthread configuration
    --enable-sp-funcs
      compile-in support for extended functions which accept a `SCREEN` pointer, reducing the need for juggling the global `SP` value with `set_term` and `delscreen`.
    --enable-term-driver
      compile with terminal-driver. That is used in the MinGW port, and (being somewhat more complicated) is an experimental alternative to the conventional termlib internals. Currently, it requires the sp-funcs feature to be enabled.
    --with-ncurses-wrap-prefix
      allows setting the prefix for functions used to wrap global variables to something other than "`_nc_`".
    --with-pkg-config=[DIR]
      check for `pkg-config`, optionally specifying its path.
    --without-manpages
      tells the configure script to suppress the install of ncurses' manpages.
    --without-tests
      suppress building test programs.
  - improved options:
    - correct logic for `--with-database`, which was coded as an enable-type switch.
    - omit the opaque-functions from `lib_gen.o` when `--disable-ext-funcs` is used.
- packaging:
  - *-config scripts:
    - modify `adacurses-config` to look for ".ali" files in the adalib directory.
    - correct install for the Ada95 tree, which omitted `libAdaCurses.a` used in `adacurses-config`.
    - change install for `adacurses-config` to provide additional flavors such as `adacursesw-config`, for ncursesw.
    - modify scripts to generate `ncurses*-config` and pc-files to add dependency for tinfo library.
    - use `ncurses*-config` scripts if available for test/configure.
    - correct name for termlib in `ncurses*-config`, e.g., if it is renamed to provide a single file for ncurses/ncursesw libraries.
    - generate manpages for the *-config scripts, adapted from `help2man`.
    - modify install-rule for manpages so that *-config manpages will install when building with `--srcdir`.
    - build-fixes for OpenSolaris aka Solaris 11, for wide-character configuration as well as for rpath feature in *-config scripts.
    - use `$includedir` symbol in `misc/ncurses-config.in`, add `--includedir` option.
    - improve install-rules for pc-files.
    - create the `pkg-config` library directory if needed.
    - fix typo "`==`" where "`=`" is needed in `ncurses-config.in` and `gen-pkgconfig.in` files.
    - modify `gen-pkgconfig.in` to eliminate a dependency on rpath when deciding whether to add `$LIBS` to `--libs` output; that should be shown for the ncurses and tinfo libraries without taking rpath into account.
    - modify handling of `$PKG_CONFIG_LIBDIR` to use only the first item in a possibly colon-separated list.
  - other packaging issues
    - add `make-tar.sh` scripts to Ada95 and test subdirectories to help with making those separately distributable.
    - add `Ada95/configure` script, to use in tar-file created by `Ada95/make-tar.sh`.
    - remove `tar-copy.sh` and related `configure/Makefile` chunks, since the Ada95 binding is now installed using rules in `Ada95/src`.
- cross-compiling:
  - improve configure checks for location of tic and infocmp programs used for installing database and for generating fallback data, e.g., for cross-compiling.
  - modify #define's for build-compiler to suppress cchar_t symbol from compile of `make_hash` and `make_keys`, improving cross-compilation of ncursesw.
  - simplify include-dependencies of `make_hash` and `make_keys`, to reduce the need for setting BUILD_CPPFLAGS in cross-compiling when the build- and target-machines differ.
  - correct cross-compiling configure check for `CF_MKSTEMP` macro, by adding a check cache variable set by `AC_CHECK_FUNC`.
- library dependencies:
  - revise `wadd_wch` and `wecho_wchar` to eliminate dependency on `unctrl`.
  - adjust configure script so that "t" is not added to library suffix when weak-symbols are used, allowing the pthread configuration to more closely match the non-thread naming.
- building the Ada95 tree:
  - changes to use gnatmake project files in the Ada95 tree.
  - add/use configure check to turn on project rules for `Ada95/src`.
  - old gnatmake (3.15) does not produce libraries using project-file; work around by adding script to generate alternate makefile.
  - add configure --with-ada-sharedlib option, for the test_make rule.
  - move Ada95-related logic into aclocal.m4, since additional checks will be needed to distinguish old/new implementations of gnat.
  - add test_make / test_clean / test_install rules in Ada95/src
  - change install-path for adainclude directory to /usr/share/ada (was /usr/lib/ada).
- other configure/build issues:
  - make `CCHARW_MAX` value configurable, noting that changing this would change the size of `cchar_t`, and would be ABI-incompatible.
  - improve comparison of program-names when checking for linked flavors such as "reset" by ignoring the executable suffix.
  - drop `mkdirs.sh`, use "`mkdir -p`".
  - drop `misc/ncu-indent` and `misc/jpf-indent`; they are provided by an external package cindent.
  - change makefiles to use `$ARFLAGS` rather than `$AR_OPTS`, provide a configure check to detect whether a "-" is needed before "ar" options.
  - modify `CF_DISABLE_LEAKS` configure macro so that the --enable-leaks option is not the same as --disable-leaks.
  - improve configure script macros `CF_HEADER_PATH` and `CF_LIBRARY_PATH` by adding `CFLAGS`, `CPPFLAGS` and `LDFLAGS`, `LIBS` values to the search-lists.
  - improve configure macros `CF_GCC_VERSION` and `CF_GCC_WARNINGS` to work with gcc 4.x's c89 alias, which gives warning messages for cases where older versions would produce an error.
  - modify `CF_WITH_LIBTOOL` configure check to allow unreleased libtool version numbers (e.g. which include alphabetic chars, as well as digits, after the final '.').
  - improve use of symbolic links in makefiles by using "`-f`" option if it is supported, to eliminate temporary removal of the target
  - add a configure-time check to pick a suitable value for `CC_SHARED_OPTS` for Solaris.
  - add -shared option to `MK_SHARED_LIB` when -Bsharable is used, for *BSD's, without which "main" might be one of the shared library's dependencies.
  - modify configure script to allow building shared libraries with gcc on AIX 5 or 6.
  - suppress configure check for static/dynamic linker flags for gcc on Solaris 10, since gcc is confused by absence of static libc, and does not switch back to dynamic mode before finishing the libraries.
  - suppress configure check for static/dynamic linker flags for gcc on Darwin.
  - modify `misc/run_tic.in` to create parent directory, in case this is a new install of hashed database.
  - modify configure check for tic program, used for fallbacks, to a warning if not found. This makes it simpler to use additonal scripts to bootstrap the fallbacks code using tic from the build tree.
- test programs:
  - add test/demo_terminfo, for comparison with demo_termcap.
  - improve test/ncurses.c 'F' test, show combining characters in color.
  - fix logic for 'V' in test/ncurses.c tests f/F.
  - improve test/ncurses.c 'a test to put mouse droppings in the proper window.
  - modify ncurses 'F' test to demo wborder_set with colored lines.
  - modify ncurses 'f' test to demo wborder with colored lines.
  - improve test/ncurses.c 'a' test, using unctrl more consistently to display meta-characters.
  - correct use of `key_name` in test/ncurses.c 'A' test, which only displays wide-characters, not key-codes since 20070612.
  - add test/clip_printw.c to illustrate how to use printw without wrapping.
  - modify test-programs, e.g,. test/view.c, to address subtle differences between Tru64/Solaris and HPUX/AIX getcchar return values.
  - add some test programs (and make these use the same special keys by sharing `linedata.h` functions): test/test_addstr.c test/test_addwstr.c test/test_addchstr.c test/test_add_wchstr.c
  - add test/xterm-256color.dat
  - modify test programs to allow them to be built with NetBSD curses.
  - fixes for test programs to build/work on HPUX and AIX, etc.

# 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.

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 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 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 256-color terminals, such as modern xterm, when configured using the `--enable-ext-colors` option.
- 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(1)/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.
- 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.
- 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.

# State of the Package

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 code has been tested with a wide variety of applications including (versions starting with those noted):

cdk
  Curses Development Kit
  http://invisible-island.net/cdk/
  http://www.vexus.ca/products/CDK/
ded
  directory-editor
  http://invisible-island.net/ded/
dialog
  the underlying application used in Slackware's setup, and the basis for similar applications on GNU/Linux.
  http://invisible-island.net/dialog/
lynx
  the character-screen WWW browser
  http://lynx.isc.org/release/
Midnight Commander
  file manager
  http://www.midnight-commander.org/
mutt
  mail utility
  http://www.mutt.org/
ncftp
  file-transfer utility
  http://www.ncftp.com/
nvi
  New vi versions 1.50 are able to use ncurses versions 1.9.7 and later.
  https://sites.google.com/a/bostic.com/keithbostic/nvi
pinfo
  Lynx-like info browser. https://alioth.debian.org/projects/pinfo/
tin
  newsreader, supporting color, MIME http://www.tin.org/

as well as some that use ncurses for the terminfo support alone:

minicom
  terminal emulator
  http://alioth.debian.org/projects/minicom/
vile
  vi-like-emacs
  http://invisible-island.net/vile/

The ncurses distribution includes a selection of test programs (including a few games).

## Who's Who and What's What

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 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>

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/ .

## Future Plans

- Extended-level XPG4 conformance, with internationalization support.
- Ports to more systems, including DOS and Windows.

We need people to help with these projects. If you are interested in working on them, please join the ncurses list.

## Other Related Resources

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.

You can find lots of information on terminal-related topics not covered in the terminfo file at Richard Shuford's archive .