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Announcing ncurses 6.0
The ncurses (new curses) library is a free software emulation of
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 is better known today as
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.
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
* 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,
* It should work readily on any ANSI/POSIX-conforming unix.
The distribution includes the library and support utilities, including
* [1]captoinfo, a termcap conversion tool
* [2]clear, utility for clearing the screen
* [3]infocmp, the terminfo decompiler
* [4]tabs, set tabs on a terminal
* [5]tic, the terminfo compiler
* [6]toe, list (table of) terminfo entries
* [7]tput, utility for retrieving terminal capabilities in shell
* [8]tset, to initialize the terminal
Full manual pages are provided for the library and tools.
The ncurses distribution is available via anonymous FTP at the GNU
distribution site
[9] .
It is also available at
[10] .
Release Notes
These notes are for ncurses 6.0, released August 8, 2015.
This release is designed to be source-compatible with ncurses 5.0
through 5.9; providing a new application binary interface (ABI).
Although the source can still be configured to support the ncurses 5
ABI, the intent of the release is to provide extensions which are
generally useful, but binary-incompatible with ncurses 5:
* Extend the cchar_t structure to allow more than 16 colors to be
* Modify the encoding of mouse state to make room for a 5th mouse
button. That allows one to use ncurses with a wheel mouse with
xterm or similar X terminal emulators.
There are, of course, numerous other improvements, including
* fixes made based on the Clang and Coverity static analyzers.
* memory leak fixes using Valgrind
The release notes mention some bug-fixes, but are focused on new
features and improvements to existing features log since ncurses 5.9
While the intent of the release is to provide a new stable ABI, there
are other development activities which are summarized below.
* The original release plan, e.g., for "5.10" was to improve the
MinGW port. Ultimately that was completed (wide-character support,
mouse, etc), but was deferred to focus on termcap support and
performance issues. Also, pinpointing the problems with Console2
took a while.
* A review of termcap compatibility in 2011 led to several minor
fixes in the library and improvements to utilities. To do this
properly, a review of the various extent termcap implementations
was needed.
The [11]termcap library checker (tctest) (not part of ncurses) was
one result. A followup review of performance using
[12]ncurses-examples in 2014 led to additional improvements.
* Output buffering provided a further, but worthwhile distraction. A
bug report in 2012 regarding the use of signal handlers in
ncurses) pointed out [13]a problem with the use of unsafe
functions for handling SIGTSTP. Other signals could be addressed
with workarounds; repairing SIGTSTP required a different approach.
The solution required changing internal behavior of the library:
how it handles output buffering.
Now ncurses buffers its own output, independently of the standard
output. A few applications relied upon the library's direct reuse
of the standard output buffering; however that is unspecified
behavior and has never been a recommended practice. Identifying
these applications as well as refining the change to permit
low-level applications to work consistently took time.
* Since the introduction of the experimental support for 256 colors
early in [14]2005 (released in [15]ncurses 5.5), there has been
increased user interest. Almost all packagers continue providing
the ncurses ABI 5 which cannot support 256 colors.
* Symbol versioning, or the lack of it in ncurses, is the main
reason why packagers would be reluctant to add a new ncurses ABI.
This release provides the new ABI along with script-generated
lists of versioned symbols which can be used for both ABI 5 and 6
(with distinct names to keep the two separate). This took time to
development, as reported in [16]Symbol versioning in ncurses.
Library improvements
Output buffering
X/Open curses provides more than one initialization function:
* [17]initscr (the simplest) accepts no parameters.
* [18]newterm accepts parameters for the stream input and output
* [19]setupterm (the low-level function) accepts a parameter for the
file descriptor of the output.
They are documented in X/Open as if initscr calls newterm using stdout
for output stream, and in turn newterm calls setupterm using
fileno(stdout) for the file descriptor. As long as an implementation
acts as if it does this, it conforms. In practice, implementations do
what is implied. This creates a problem: the low-level setupterm
function's file descriptor is unbuffered, while newterm implies
buffered output. X/Open Curses says that all output is done through
the file descriptor, and does not say how the output stream is
actually used.
Initially, ncurses used the file descriptor (obtained from the output
stream passed to newterm) for changing the terminal modes, and relied
upon the output parameter of newterm for buffered output. Later (to
avoid using unsafe buffered I/O in signal handlers), ncurses was
modified to use the file descriptor (unbuffered output) when cleaning
up on receipt of a signal. Otherwise (when not handling a signal), it
continued to use the buffered output.
That approach worked reasonably well and as a side effect, using the
same buffered output as an application might use for printf meant that
no flushing was needed when switching between normal- and
There were a couple of problems:
* to get good performance, curses (not only ncurses, but SVr4 curses
in general) set an output buffer using setbuf or similar function.
There is no standard (or portable) way to turn that output buffer
off, and revert to line-buffering. The [20]NCURSES_NO_SETBUF
environment variable did make it optional.
* to handle SIGTSTP (the "stop" signal), ncurses relied upon unsafe
functions. That is, due to the complexity of the feature, it
relied upon reusing existing functions which should not have been
called via the signal handler.
Conveniently, solving the second problem (by making ncurses do its own
output buffering) also fixed the first one. But there were special
cases to resolve: [21]low-level functions such as mvcur, putp, vidattr
explicitly use the standard output. Those functions were reused
internally, and required modification to distinguish whether they were
used by the high-level or low-level interfaces.
Finally, there may still be a few programs which should be modified to
improve their portability, e.g., adding an
when switching from "[22]shell" mode to "[23]program" (curses) mode.
Those are fairly rare because most programmers have learned not to mix
printf and [24]printw.
Symbol versioning
This release introduces symbol-versioning to ncurses because without
it, the change of ABI would be less successful. A lengthy discussion
will be presented in [25]Symbol versioning in ncurses. These notes
summarize what has changed, and what can be done with the new release.
Symbol-versioning allows the developers of a library to mark each
public symbol (both data and functions) with an identifier denoting
the library name and the version for which it was built. By doing
this, users of the library have a way to help ensure that applications
do not accidentally load an incompatible library. In addition, private
symbols can be hidden entirely.
This release provides sample files for the four principal
configurations of ncurses libraries: ncurses, ncursesw, ncursest and
ncursestw. Each sample is given in two forms:
These list all public symbols, together with version names.
These list all public symbols, without version names.
The sample files are generated by scripts which take into account a
few special cases such as [26]tack to omit many of the ncurses private
symbols (beginning with "_nc_"). Here are counts of globals versus
Config Symbols Globals Locals "_nc_"
ncurses 976 796 180 332
ncursesw 1089 905 184 343
ncursest 979 804 175 358
ncursestw 1098 914 184 372
Although only four sample configurations are presented, each is formed
by merging symbols from several combinations of configure-script
options, taking into account advice from downstream packagers. Because
they are formed by merging, the sample files may list a symbol which
is not in a given package. That is expected. The samples have been
tested and are working with systems (such as Fedora, FreeBSD and
Debian) which fully support this feature. There are other systems
which do not support the feature, and a few (such as Solaris) which
provide incomplete support.
The version-naming convention used allows these sample files to build
distinct libraries for ABI 5 and 6. Version names consist of
* configuration name, e.g., "NCURSESW" for the wide-character
* ABI version (if not 5)
* library name for two special cases which have the same interface
across configurations: "TINFO" and "TIC"
* release version
* patch date (for the release version)
For example, running nm -D on the libraries in the ncurses6 test
package shows these symbol-versions:
0000000000000000 A NCURSES6_TIC_5.0.19991023
0000000000000000 A NCURSES6_TIC_5.1.20000708
0000000000000000 A NCURSES6_TIC_5.5.20051010
0000000000000000 A NCURSES6_TIC_5.7.20081102
0000000000000000 A NCURSES6_TIC_5.9.20150530
0000000000000000 A NCURSES6_TINFO_5.0.19991023
0000000000000000 A NCURSES6_TINFO_5.1.20000708
0000000000000000 A NCURSES6_TINFO_5.2.20001021
0000000000000000 A NCURSES6_TINFO_5.3.20021019
0000000000000000 A NCURSES6_TINFO_5.4.20040208
0000000000000000 A NCURSES6_TINFO_5.5.20051010
0000000000000000 A NCURSES6_TINFO_5.6.20061217
0000000000000000 A NCURSES6_TINFO_5.7.20081102
0000000000000000 A NCURSES6_TINFO_5.8.20110226
0000000000000000 A NCURSES6_TINFO_5.9.20150530
0000000000000000 A NCURSESW6_5.1.20000708
0000000000000000 A NCURSESW6_5.3.20021019
0000000000000000 A NCURSESW6_5.4.20040208
0000000000000000 A NCURSESW6_5.5.20051010
0000000000000000 A NCURSESW6_5.6.20061217
0000000000000000 A NCURSESW6_5.7.20081102
0000000000000000 A NCURSESW6_5.8.20110226
0000000000000000 A NCURSESW6_5.9.20150530
As a special case, this release (which makes the final change for ABI
5) is marked with release version 5.9 and patch date 20150530.
The new release has several improvements for performance and building.
For instance:
* several files in ncurses- and progs-directories were modified to
allow const data used in internal tables to be put by the linker
into the readonly text segment.
* various improvements were made to building the Ada95 binding, both
in simplifying the generated files as well as improving the way it
uses gnatmake
There are also new features in the libraries:
* added [27]use_tioctl function
* added [28]wgetdelay to retrieve _delay member of WINDOW if it
happens to be opaque, e.g., in the pthread configuration.
* added [29]A_ITALIC extension.
* added form library extension [30]O_DYNAMIC_JUSTIFY option which
can be used to override the different treatment of justification
for static versus dynamic fields .
* rewrote [31]putwin and [32]getwin, making an extended version
which is capable of reading screen-dumps between the wide/normal
ncurses configurations. These are text files, except for a magic
code at the beginning:
0 string \210\210 Screen-dump (ncurses)
* several changes to mouse support include:
+ added decoder for xterm SGR 1006 mouse mode.
+ added experimental support for "%u" format to terminfo.
+ improved behavior of wheel-mice for xterm protocol: noting
that there are only button-presses for buttons "4" and "5",
so there is no need to wait to combine events into
double-clicks .
There are a few new configure options dealing with library
* add "--enable-ext-putwin" configure option to turn on the extended
putwin/getwin. By default, this is enabled for ABI 6 and disabled
with ABI 5.
* add "--enable-string-hacks" option to control whether strlcat and
strlcpy may be used. Because ncurses already does the requisite
buffer-limit checks, this feature is mainly of interest to quiet
compiler-warnings on a few systems.
* add configure option "--with-tparm-arg" to allow [33]tparm's
parameters to be something more likely to be the same size as a
pointer, e.g., intptr_t (again, the default is set for ABI 6).
Program improvements
Most of the termcap-related changes based on development of [34]tctest
(termcap library checker) are implemented in the tic and infocmp
programs rather than affecting the library. As noted in the
[35]discussion of tctest, ncurses's ability to translate between
terminfo and termcap formats has been improved at different times, but
subject to feedback from "real" termcap users. There are very few of
those. Nowadays, virtually all termcap users are using ncurses (or
NetBSD, with its own terminfo library) and their programs are actually
using terminfo rather than termcap data.
Still, there are a few. A comment about the translation of the ASCII
NUL character prompted a review:
* Both terminfo and termcap store string capabilities as
NUL-terminated strings.
* In terminfo, a \0 in a terminal description is stored as \200.
* There are no (known) terminals which would behave differently when
sent \0 or \200.
* When translating to terminfo format (or displaying a printable
version of an entry using infocmp), ncurses shows \200 as \0.
* It has done this since 1998 (quoting from the NEWS file):
+ modify _nc_tic_expand() to generate \0 rather than \200.
+ correct translation of terminfo "^@", to \200, like \0.
* However, the _nc_tic_expand function (which optionally produces
terminfo or termcap format) did not address this special case for
termcap. Even the later 4.4BSD [37]cgetstr interprets a \0
literally, ending that string (rather than using the terminfo
As a result of the review, several improvements were made to ncurses
translation to/from termcap format -- and improving the checks made in
tic for consistency of entries. Most of these are not of general
interest, except for two new command-line options for tic and infocmp:
* the "-0" option generates termcap/terminfo source on a single
* the "-K" option provides stricter BSD-compatibility for termcap
Other user-visible improvements and new features include:
* added "-D" option to tic and infocmp, to show the database
locations that it could use.
* added "-s" option to toe, to sort its output.
* extended "-c" and "-n" options of infocmp to allow comparing more
than two entries.
* modified toe's report when "-a" and "-s" options are combined, to
add a column showing which entries belong to a given database.
* modified the clear program to take into account the "E3" extended
capability to clear the terminal's scrollback buffer.
Along with the library and utilities, many improvements were made to
the [38]ncurses-examples. Some were made to allow building (and
comparison-testing) against NetBSD curses and PDCurses. Both lack some
of the X/Open Curses features, necessitating customization. But this
activity was useful because it showed some remaining performance
issues (which have been resolved in this release).
These changes were made to verify compatibility or compare performance
of ncurses:
* made workarounds for compiling test-programs with NetBSD curses,
though it lacks some common functions such as [39]use_env.
* added dots_termcap test-program
* added dots_curses test-program, for comparison with the low-level
* added test_setupterm test-proram to demonstrate normal/error
returns from the setupterm and restartterm functions.
* added "-d", "-e" and "-q" options to the demo_terminfo and
demo_termcap test-programs.
* added "-y" option to demo_termcap and test/demo_terminfo
test-programs to demonstrate behavior with/without extended
* modified demo_termcap and demo_terminfo test-programs to make
their options more directly comparable, and add "-i" option to
specify a terminal description filename to parse for names to
* rewrote the tests for [40]mvderwin and test for recursive
[41]mvwin in the movewindow test-program.
These changes were made to help with the MinGW port:
* added test-screens to the ncurses test-program to show
256-characters at a time, to help with MinGW port.
* modified the view test-program to load UTF-8 when built with MinGW
by using regular win32 API because the MinGW functions mblen and
mbtowc do not work.
* added "-s" option to the view test-program to allow it to start in
single-step mode, reducing size of trace files when it is used for
debugging MinGW changes.
These changes were made to verify new extensions in ncurses:
* added [42]form_driver_w entrypoint to wide-character forms
library, as well as form_driver_w test-program.
* modified ncurses test-program's b/B tests to display lines only
for the attributes which a given terminal supports, to make room
for an italics test.
* modified ncurses test-program, adding "-E" and "-T" options to
demonstrate use_env versus use_tioctl.
* modified ncurses test-program's c/C tests to cycle through subsets
of the total number of colors, to better illustrate
8/16/88/256-colors by providing directly comparable screens.
* modified the ncurses test-program to also show position reports in
'a' test.
These changes were made to make the examples more useful:
* added scripts for building dpkg and rpm test-packages
* modified the hanoi test-program to show the minimum number of
moves possible for the given number of tiles.
* modified the knight test-program to show the number of choices
possible for each position in automove option, e.g., to allow user
to follow Warnsdorff's rule to solve the puzzle.
Terminal database
This release provides improvements to tic's "-c" checking option,
which was used for example to
* make sgr in several entries agree with other caps.
* correct padding in some entries where earlier versions had
miscounted the number of octal digits.
There are several new terminal descriptions:
* [43]mlterm is now aliased to mlterm3
* [44]nsterm is now derived from nsterm-256color
* [45]putty-sco
* [46]teken is FreeBSD's "xterm" console.
* [47]terminator
* [48]terminology
* [49]tmux is derived from screen.
* several screen.XXX entries support the respective variations for
256 colors.
* [50]simpleterm is now 0.5
* [51]vte is aliased to vte-2012
* [52]vt520ansi
A few entries use extensions (user-defined terminal capabilities):
* E3, used in linux, putty and xterm-basic is tested in the
[53]clear program to erase a terminal's scrollback.
* TS is used in the [54]xterm+sl building block to help deprecate
the misuse of tsl for xterm's title-string.
* XT is used in some terminfo entries to improve usefulness for
other applications than screen, which would like to pretend that
xterm's title is a status-line.
* xm is used in examples [55]xterm-1005 and [56]xterm-1006 to
illustrate a way to make mouse handling more general
A few terminals support italics and/or dim capabilities. In
particular, screen does not. Documented that, and accommodated the
terminals where this feature works with the A_ITALIC extension.
* konsole, mlterm3 (italics)
* nsterm (dim)
* screen (dim)
* vte (dim, italics)
* xterm (dim, italics)
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 [57]NEWS file but treated sketchily in manual pages.
In addition, the mechanism for producing HTML versions of the
documentation has been improved:
* use an improved version of [58]man2html to generate html manpages.
* regenerated [59]NCURSES-Programming-HOWTO.html to fix some of the
broken html emitted by docbook.
Interesting bug-fixes
* Ada95 binding:
+ modify makefile rules to ensure that the PIC option is not
used when building a static library
+ make Ada95 build-fix for big-endian architectures such as
sparc. This undoes one of the fixes from [60]20110319, which
added an "Unused" member to representation clauses, replacing
that with pragmas to suppress warnings about unused bits.
* Color and attributes:
+ parenthesize parameter of COLOR_PAIR and PAIR_NUMBER in
curses.h in case it happens to be a comma-expression.
+ improve [61]20021221 workaround for broken acs, handling a
case where that ACS_xxx character is not in the acsc string
but there is a known wide-character which can be used.
+ modify [62]init_pair to accept -1's for color value after
[63]assume_default_colors has been called.
+ add a check in [64]start_color to limit color-pairs to 256
when extended colors are not supported.
* Resizing the screen:
+ propagate error-returns from wresize, i.e., the internal
increase_size and decrease_size functions through
+ add check for zero/negative dimensions for resizeterm and
+ modify resizeterm to always push a KEY_RESIZE onto the fifo,
even if screensize is unchanged. Modify library to push a
KEY_RESIZE if there was a SIGWINCH, even if it does not call
resizeterm). These changes eliminate the case where a
SIGWINCH is received, but ERR is returned from wgetch or
wgetnstr because the screen dimensions did not change.
* Low-level interfaces
+ fix an old bug in the termcap emulation; "%i" was ignored in
tparm because the parameters to be incremented were already
on the internal stack.
+ change "%l" behavior in tparm to push the string length onto
the stack rather than saving the formatted length into the
output buffer.
+ modify name-comparison for tgetstr, etc., to accommodate
legacy applications as well as to improve compatbility with
BSD 4.2 termcap implementations (see note for [66]980725).
* High-level interfaces
+ modify internal recursion in wgetch which handles cooked mode
to check if the call to wgetnstr returned an error. This can
happen when both nocbreak and nodelay are set, for instance
(see note for [67]960418).
+ add a check in internal function waddch_nosync to ensure that
tab characters are treated as control characters; some broken
locales claim they are printable.
+ modify menu library to ensure that a menu's top-row is
adjusted as needed to ensure that the current item is on the
+ fix special case where double-width character overwrites a
single- width character in the first column.
Configuration changes
Major changes
The ncurses 6.0 configure script makes changes to the default value of
several configure options, depending on the --with-abi-version option
(i.e., whether its value is "5" or "6"):
Feature introduced in [68]970405 supports the use of const
where X/Open Curses should have, but did not. NetBSD curses
does something similar with const.
Extends the cchar_t structure to allow more than 16 colors to
be encoded. This applies only to the wide-character
(--enable-widec) configuration.
Modifies the encoding of mouse state to make room for a 5th
mouse button. That allows one to use ncurses with a wheel mouse
with xterm or similar X terminal emulators.
Modifies the file-format written by putwin to use printable
text rather than binary files, allowing getwin to read screen
dumps written by differently-configured ncurses libraries. The
extended getwin can still read binary screen dumps from the
same configuration of ncurses. This does not change the ABI
(the binary interface seen by calling applications).
Modifies the FIELDTYPE structure used for the form library to
make it more generic.
Allows an application to define _LP64 to declare chtype and
mmask_t as simply "unsigned" rather than the configured types
using the --with-chtype and --with-mmask_t options.
Compile-in support for extended functions which accept a SCREEN
pointer, reducing the need for juggling the global SP value
with [69]set_term and [70]delscreen.
Makes chtype explicitly a 32-bit unsigned value.
Makes mmask_t explicitly a 32-bit unsigned value.
X/Open Curses declares [71]tparm using long for each of the
parameters aside from the formatting string, presuming that
long and char* are the same size. This configure option uses
intptr_t which provides a better guarantee of the sizes.
The configure script no longer checks for antique compilers; c89 is
assumed as a minimum. There are a few features from later revisions
which are used when available. The configure script makes checks to
turn on useful warnings from clang, gcc and icc. You should be able to
build ncurses 6.0 with any of the current (or not so current) C
compilers available in 2015.
The configure script, by the way, makes changes which do not work with
systems whose /bin/sh is non-POSIX. This mainly affects Solaris (the
other vendor unix systems have followed the POSIX guidelines for the
past twenty years). If you must build on Solaris, its [72]xpg4
binaries suffice, e.g.,
WHAT=`hostname|sed -e 's/\..*//'`
cat >>$OUT <<EOF/
** `date`
** node: $WHAT
** user: `id`
** conf: $*
if test -f /usr/xpg4/bin/sh
rm -f config.status config.cache
$SHELL ./configure --verbose \
--disable-echo \
--disable-overwrite \
--enable-warnings \
--with-warnings \
--prefix=$TOP $* 2>&1 | tee -a $OUT
Other major changes to the configure script include:
* ABI 6 is now the default, intending that the existing ABI 5 should
build as before using the "--with-abi-version=5" option.
* added --with-extra-suffix option to help with installing
nonconflicting ncurses6 packages, e.g., avoiding header- and
NOTE: as a side-effect, this renames
adacurses-config to adacurses5-config and
adacursesw-config to adacursesw5-config
* the configure script looks for gnatgcc if the Ada95 binding is
built, in preference to the default gcc/cc. The script also
ensures that the Ada95 binding is built with the level of
optimization as the C libraries.
* the configure script captures define's related to -D_XOPEN_SOURCE
from the configure check and adds those to the *-config and *.pc
files, to simplify use for the wide-character libraries.
Configuration options
There are several new (or extended) configure options:
Do not install the terminal database. This is used to omit
features for packages, as done with --without-progs. The option
simplifies building cross-compile support packages.
This option is used for regression testing
Suppress the "w", "t" or "tw" suffixes which normally would be
added to the library names for the --enable-widec and
--with-pthread options.
When --with-shared is set, build libncurses++ as a shared
library. This implicitly relies upon building with gcc/g++,
since other compiler suites may have differences in the way
shared libraries are built. libtool by the way has similar
Extended this configure option to simplify building with
different versions of Berkeley database using FreeBSD ports.
If ".pc" files are installed, optionally add a suffix to the
files and corresponding package names to separate unusual
configurations. If no option value is given (or if it is
"none"), no suffix is added. This option is used in the test
package for ncurses6.
Configure xterm's terminfo entries to use either BS (^H, i.e.,
ASCII backspace) or DEL (^?, or 127).
Most of the portability-related work since [73]ncurses 5.9 extended
and improved the MinGW port introduced in [74]ncurses 5.8.
The MinGW port can be readily cross-compiled:
* modified configure script to allow creating dll's for MinGW when
* enforced Windows-style path-separator if cross-compiling,
* added scripts for test-builds of cross-compiled packages for
ncurses6 to MinGW.
* added pc-files to the MinGW cross-compiling test-packages.
* added script for building test-packages of binaries cross-compiled
to MinGW using NSIS.
* added nc_mingw.h to installed headers for MinGW port; this is
needed for cross-compiling [75]ncurses-examples.
* added test-packages for cross-compiling ncurses-examples using the
MinGW test-packages.
The MinGW-specific Windows driver accounts for several changes:
* wide-character display is made usable by replacing MinGW's
non-working wcrtomb and wctomb functions.
* implemented some display features: [76]beep, [77]flash,
* the driver handles repainting on endwin/refresh combination.
* modified treatment of TERM variable for MinGW port to allow
explicit use of the Windows console driver by checking if $TERM is
set to "#win32console" or an abbreviation of that.
* the Windows driver also matches the special TERM value "unknown"
* the driver now returns characters for special keys, (like ansi.sys
does), when keypad mode is off, rather than returning nothing at
* the driver checks a new environment variable [79]NCURSES_CONSOLE2
to optionally work around a deficiency in Console2 (and its
descendent ConsoleZ) which hang when an application creates a
console buffer.
Finally, there are other improvements:
* MinGW is one of the configurations where ncurses installs by
default into /usr
* configuration for cross-compiling uses AC_CHECK_TOOLS in
preference to AC_PATH_PROGS when searching for ncurses*-config,
e.g., in Ada95/configure and test/configure.
* extend Windows support to work with MSYS2;
+ this works with a scenario where there is an ANSI-escape
handler such as ansicon running in the console window.
+ wrap isatty calls with a macro, provide a corresponding set
of support routines to address differences between MinGW and
* ensure WINVER is defined in makefiles rather than using headers.
* add check for the gnatprep "-T" option.
* work around a bug introduced by [80]gcc 4.8.1 in MinGW which
breaks "trace" feature.
* add a driver-name method to each of the drivers.
Other ports
These changes affect certain platforms (ports):
* the configure script knows how to build shared libraries with
DragonFlyBSD and Interix.
* support for AIX shared libraries is improved, tested with AIX 5.3,
6.1 and 7.1 with both gcc 4.2.4 and cc:
+ the shared-library suffix for AIX 5 and 6 is now ".so"
+ the -brtl option is used with AIX 5-7; it is needed to link
with the shared libraries.
* the configure --enable-pc-files option takes into account the
[81]PKG_CONFIG_PATH variable.
* the configure option --with-pkg-config-libdir provides control
over the actual directory into which pc-files are installed.
* the build scripts add explicit -ltinfo, etc., to the generated
".pc" file when ld option "--as-needed" is used, or when ncurses
and tinfo are installed without using rpath.
* the configure script disallows conflicting options
"--with-termlib" and "--enable-term-driver".
* the check for missing c++ compiler to work when no error is
reported, and no variables set is improved (see note for
* the misc/ script selects a "linux" entry which works
with the current kernel rather than assuming it is always
* the test/configure script makes it simpler to override names of
curses-related libraries, to help with linking with pdcurses in
MinGW environment.
* the configure-script/ifdef's allow the BSD OLD_TTY feature to be
suppressed if the type of ospeed is configured using the option
--with-ospeed to not be a short. By default, it is a short for
* the script works around a recent change in gcc 5
(released [83]mid-2015) which essentially emits multiple #line
statements for the same position in a file.
* the configure script works with Minix3.2 (see [84]note on
* OS/2 redux:
+ the configure script supports OS/2 kLIBC.
+ the --with-lib-prefix option allows configuring for old/new
flavors of OS/2 EMX.
* improved configure-script checks for _XOPEN_SOURCE:
+ the definition works starting with Solaris 10.
+ the definition is suppressed for IRIX64, since its header
files have a conflict versus _SGI_SOURCE.
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
+ 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
* 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 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
* 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
* 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 [85]tic/[86]captoinfo utility provided with ncurses has the
ability to translate many termcaps from the XENIX, IBM and AT&T
extension sets.
* A BSD-like [87]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
* 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 [88]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
* Extensive documentation is provided (see the [89]Additional
Reading section of the [90]ncurses FAQ for online documentation).
Applications using ncurses
The ncurses distribution includes a selection of test programs
(including a few games). These are available separately as
The ncurses library has been tested with a wide variety of
applications including:
Curses Development Kit
the underlying application used in Slackware's setup, and the
basis for similar install/configure applications on many
the text WWW browser
Midnight Commander
file manager
mail utility
file-transfer utility
New vi uses ncurses.
newsreader, supporting color, MIME
as well as some that use ncurses for the terminfo support alone:
terminal emulator for serial modem connections
a replacement for ssh.
terminfo action checker
terminal multiplexor
vi-like-emacs may be built to use the terminfo, termcap or
curses interfaces.
and finally, those which use only the termcap interface:
text editor
terminal multiplexor
text editor
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 [109]Thomas Dickey. Thomas Dickey also
acts as the maintainer for the Free Software Foundation, which holds
the [110]copyright on ncurses.
Contact the current maintainers at
To join the ncurses mailing list, please write email to
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
[113] .
There is an archive of the mailing list here:
[114] (also
Related resources
The release notes make scattered references to these pages, which may
be interesting by themselves:
* [116]man2html
* [117]ncurses licensing
* [118]Symbol versioning in ncurses
* [119]The MinGW port of ncurses
* [120]tack - terminfo action checker
* [121]tar versus portability
* [122]tctest - termcap library checker
* [123]Terminal Database
Other resources
The distribution provides a newer version of the terminfo-format
terminal description file once maintained by [124]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 [125]Richard Shuford's archive .
* [126]Overview
* [127]Release Notes
+ [128]Library improvements
o [129]Output buffering
o [130]Symbol versioning
o [131]Miscellaneous
+ [132]Program improvements
o [133]Utilities
o [134]Examples
+ [135]Terminal database
+ [136]Documentation
+ [137]Interesting bug-fixes
+ [138]Configuration changes
o [139]Major changes
o [140]Configuration options
+ [141]Portability
o [142]MinGW
o [143]Other ports
* [144]Features of ncurses
* [145]Applications using ncurses
* [146]Development activities
* [147]Related resources
* [148]Other resources
117. http://invisible-island.net
126. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h2-overview
127. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h2-release-notes
128. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h3-library
129. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h3-lib-setbuf
130. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h3-lib-versioning
131. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h3-lib-other
132. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h3-programs
133. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h4-utilities
134. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h4-examples
135. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h3-database
136. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h3-documentation
137. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h3-bug-fixes
138. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h3-config-config
139. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h4-config-major
140. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h4-config-options
141. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h3-portability
142. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h4-port-mingw
143. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h4-port-systems
144. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h2-features
145. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h2-who-uses
146. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h2-development
147. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h2-this-stuff
148. file:///usr/build/ncurses/ncurses-6.0-20150808/doc/html/announce.html#h2-other-stuff