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<h1 class="no-header">Announcing ncurses @VERSION@</h1>
<h2><a name="h2-overview" id="h2-overview">Overview</a></h2>
<p>The <em class="small-caps">ncurses</em> (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.</p>
<p>In mid-June 1995, the maintainer of 4.4BSD curses declared
that he considered 4.4BSD curses obsolete, and encouraged the
keepers of <em class="small-caps">unix</em> releases such as
BSD/OS, FreeBSD and NetBSD to switch over to <em class=
"small-caps">ncurses</em>.</p>
<p>Since 1995, <em class="small-caps">ncurses</em> has been
ported to many systems:</p>
<ul>
<li>It is used in almost every system based on the Linux kernel
(aside from some embedded applications).</li>
<li>It is used as the system curses library on OpenBSD, FreeBSD
and OSX.</li>
<li>It is used in environments such as Cygwin and MinGW. The
first of these was EMX on OS/2 Warp.</li>
<li>It is used (though usually not as the <em>system</em>
curses) on all of the vendor <em class="small-caps">unix</em>
systems, e.g., AIX, HP-UX, IRIX64, SCO, Solaris, Tru64.</li>
<li>It should work readily on any ANSI/POSIX-conforming
<em class="small-caps">unix</em>.</li>
</ul>
<p>The distribution includes the library and support utilities,
including</p>
<ul>
<li><a href=
"http://invisible-island.net/ncurses/man/captoinfo.1m.html">captoinfo</a>,
a termcap conversion tool</li>
<li><a href=
"http://invisible-island.net/ncurses/man/clear.1.html">clear</a>,
utility for clearing the screen</li>
<li><a href=
"http://invisible-island.net/ncurses/man/infocmp.1m.html">infocmp</a>,
the terminfo decompiler</li>
<li><a href=
"http://invisible-island.net/ncurses/man/tabs.1.html">tabs</a>,
set tabs on a terminal</li>
<li><a href=
"http://invisible-island.net/ncurses/man/tic.1m.html">tic</a>,
the terminfo compiler</li>
<li><a href=
"http://invisible-island.net/ncurses/man/toe.1m.html">toe</a>,
list (table of) terminfo entries</li>
<li><a href=
"http://invisible-island.net/ncurses/man/tput.1.html">tput</a>,
utility for retrieving terminal capabilities in shell
scripts</li>
<li><a href=
"http://invisible-island.net/ncurses/man/tset.1.html">tset</a>,
to initialize the terminal</li>
</ul>
<p>Full manual pages are provided for the library and tools.</p>
<p>The <em class="small-caps">ncurses</em> distribution is
available via anonymous FTP at the GNU distribution site</p>
<blockquote>
<p><a href=
"ftp://ftp.gnu.org/gnu/ncurses/">ftp://ftp.gnu.org/gnu/ncurses/</a>&nbsp;.</p>
</blockquote>It is also available at
<blockquote>
<p><a href=
"ftp://invisible-island.net/ncurses/">ftp://invisible-island.net/ncurses/</a>&nbsp;.</p>
</blockquote>
<h2><a name="h2-release-notes" id="h2-release-notes">Release
Notes</a></h2>
<p>These notes are for <em class="small-caps">ncurses</em>
@VERSION@, released <strong>August 8, 2015</strong>.</p>
<p>This release is designed to be source-compatible with
<em class="small-caps">ncurses</em> 5.0 through 5.9; providing a
new application binary interface (ABI). Although the source can
still be configured to support the <em class=
"small-caps">ncurses</em> 5 ABI, the intent of the release is to
provide extensions which are generally useful, but
binary-incompatible with <em class="small-caps">ncurses</em>
5:</p>
<ul>
<li>
<p>Extend the <code>cchar_t</code> structure to allow more
than 16 colors to be encoded.</p>
</li>
<li>
<p>Modify the encoding of mouse state to make room for a 5th
mouse button. That allows one to use <em class=
"small-caps">ncurses</em> with a wheel mouse with xterm or
similar X terminal emulators.</p>
</li>
</ul>
<p>There are, of course, numerous other improvements,
including</p>
<ul>
<li>
<p>fixes made based on the Clang and Coverity static
analyzers.</p>
</li>
<li>
<p>memory leak fixes using Valgrind</p>
</li>
</ul>
<p>The release notes mention some bug-fixes, but are focused on
new features and improvements to existing features log since
<em class="small-caps">ncurses</em> 5.9 release.</p>
<p>While the intent of the release is to provide a new stable
ABI, there are other development activities which are summarized
below.</p>
<ul>
<li>
<p>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 <code>Console2</code> took a while.</p>
</li>
<li>
<p>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.</p>
<p>The <a href=
"http://invisible-island.net/ncurses/tctest.html">termcap
library checker (tctest)</a> (not part of <em class=
"small-caps">ncurses</em>) was one result. A followup review
of performance using <a href=
"http://invisible-island.net/ncurses/ncurses-examples.html">ncurses-examples</a>
in 2014 led to additional improvements.</p>
</li>
<li>
<p>Output buffering provided a further, but worthwhile
distraction. A bug report in 2012 regarding the use of signal
handlers in <em class="small-caps">ncurses</em>) pointed out
<a href=
"http://lists.gnu.org/archive/html/bug-ncurses/2012-07/msg00029.html">
a problem</a> with the use of unsafe functions for handling
<code>SIGTSTP</code>. Other signals could be addressed with
workarounds; repairing <code>SIGTSTP</code> required a
different approach. The solution required changing internal
behavior of the library: how it handles output buffering.</p>
<p>Now <em class="small-caps">ncurses</em> 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
<em>unspecified</em> 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.</p>
</li>
<li>
<p>Since the introduction of the experimental support for 256
colors early in <a href=
"http://invisible-island.net/ncurses/NEWS.html#t20050101">2005</a>
(released in <a href=
"http://invisible-island.net/ncurses/announce-5.5.html">ncurses
5.5</a>), there has been increased user interest. Almost all
packagers continue providing the ncurses ABI 5 which cannot
support 256 colors.</p>
</li>
<li>
<p>Symbol versioning, or the lack of it in ncurses, is the
main reason why packagers would be reluctant to add a new
ncurses ABI.</p>
<p>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
<a href=
"http://invisible-island.net/ncurses/ncurses-mapsyms.html">Symbol
versioning in <em class="small-caps">ncurses</em></a>.</p>
</li>
</ul>
<h3><a name="h3-library" id="h3-library">Library
improvements</a></h3>
<h3><a name="h3-lib-setbuf" id="h3-lib-setbuf">Output
buffering</a></h3>
<p>X/Open curses provides more than one initialization
function:</p>
<ul>
<li><a href=
"http://invisible-island.net/ncurses/man/curs_initscr.3x.html#h3-initscr">
initscr</a> (the simplest) accepts no parameters.</li>
<li><a href=
"http://invisible-island.net/ncurses/man/curs_initscr.3x.html#h3-newterm">
newterm</a> accepts parameters for the stream input and
output</li>
<li><a href=
"http://invisible-island.net/ncurses/man/curs_terminfo.3x.html#h3-Initialization">
setupterm</a> (the low-level function) accepts a parameter for
the <em>file descriptor</em> of the output.</li>
</ul>
<p>They are documented in X/Open <em>as if</em>
<code>initscr</code> calls <code>newterm</code> using
<code>stdout</code> for output stream, and in turn
<code>newterm</code> calls <code>setupterm</code> using
<code>fileno(stdout)</code> for the file descriptor. As long as
an implementation acts <em>as if</em> it does this, it conforms.
In practice, implementations do what is implied. This creates a
problem: the low-level <code>setupterm</code> function's file
descriptor is unbuffered, while <code>newterm</code> 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.</p>
<p>Initially, <em class="small-caps">ncurses</em> used the file
descriptor (obtained from the output stream passed to
<code>newterm</code>) for changing the terminal modes, and relied
upon the output parameter of <code>newterm</code> for buffered
output. Later (to avoid using unsafe buffered I/O in signal
handlers), <em class="small-caps">ncurses</em> 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.</p>
<p>That approach worked reasonably well and as a side effect,
using the same buffered output as an application might use for
<code>printf</code> meant that no flushing was needed when
switching between normal- and screen-modes.</p>
<p>There were a couple of problems:</p>
<ul>
<li>
<p>to get good performance, curses (not only <em class=
"small-caps">ncurses</em>, but SVr4 curses in general) set an
output buffer using <code>setbuf</code> or similar function.
There is no standard (or portable) way to turn that output
buffer off, and revert to line-buffering. The <code><a href=
"http://invisible-island.net/ncurses/man/ncurses.3x.html#h3-NCURSES_NO_SETBUF">
NCURSES_NO_SETBUF</a></code> environment variable did make it
optional.</p>
</li>
<li>
<p>to handle <code>SIGTSTP</code> (the &ldquo;stop&rdquo;
signal), <em class="small-caps">ncurses</em> 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.</p>
</li>
</ul>
<p>Conveniently, solving the second problem (by making <em class=
"small-caps">ncurses</em> do its <em>own</em> output buffering)
also fixed the first one. But there were special cases to
resolve: <a href=
"http://invisible-island.net/ncurses/man/curs_terminfo.3x.html"><em>
low-level</em></a> 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.</p>
<p>Finally, there may still be a few programs which should be
modified to improve their portability, e.g., adding an</p>
<blockquote>
<pre class="code-block">
fflush(stdout);
</pre>
</blockquote>
<p>when switching from &ldquo;<a href=
"http://invisible-island.net/ncurses/man/curs_kernel.3x.html#h3-reset_prog_mode_-reset_shell_mode">shell</a>&rdquo;
mode to &ldquo;<a href=
"http://invisible-island.net/ncurses/man/curs_kernel.3x.html#h3-reset_prog_mode_-reset_shell_mode">program</a>&rdquo;
(curses) mode. Those are fairly rare because most programmers
have learned not to mix <code>printf</code> and <code><a href=
"http://invisible-island.net/ncurses/man/curs_printw.3x.html">printw</a></code>.</p>
<h3><a name="h3-lib-versioning" id="h3-lib-versioning">Symbol
versioning</a></h3>
<p>This release introduces symbol-versioning to <em class=
"small-caps">ncurses</em> because without it, the change of ABI
would be less successful. A lengthy discussion will be presented
in <a href=
"http://invisible-island.net/ncurses/ncurses-mapsyms.html">Symbol
versioning in <em class="small-caps">ncurses</em></a>. These
notes summarize what has changed, and what can be done with the
new release.</p>
<p>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.</p>
<p>This release provides sample files for the four principal
configurations of <em class="small-caps">ncurses</em> libraries:
<code>ncurses</code>, <code>ncursesw</code>,
<code>ncursest</code> and <code>ncursestw</code>. Each sample is
given in two forms:</p>
<blockquote>
<dl>
<dt>&ldquo;<code>.map</code>&rdquo;</dt>
<dd>These list all public symbols, together with version
names.</dd>
<dt>&ldquo;<code>.sym</code>&rdquo;</dt>
<dd>These list all public symbols, without version
names.</dd>
</dl>
</blockquote>
<p>The sample files are <em>generated</em> by scripts which take
into account a few special cases such as <a href=
"http://invisible-island.net/ncurses/tack.html">tack</a> to omit
many of the <em class="small-caps">ncurses</em> private symbols
(beginning with &ldquo;<code>_nc_</code>&rdquo;). Here are
counts of globals versus locals:</p>
<blockquote>
<table border="1" summary="Total global and local symbols">
<tr>
<th>Config</th>
<th>Symbols</th>
<th>Globals</th>
<th>Locals</th>
<th>"_nc_"</th>
</tr>
<tr>
<td>ncurses</td>
<td align="right">976</td>
<td align="right">796</td>
<td align="right">180</td>
<td align="right">332</td>
</tr>
<tr>
<td>ncursesw</td>
<td align="right">1089</td>
<td align="right">905</td>
<td align="right">184</td>
<td align="right">343</td>
</tr>
<tr>
<td>ncursest</td>
<td align="right">979</td>
<td align="right">804</td>
<td align="right">175</td>
<td align="right">358</td>
</tr>
<tr>
<td>ncursestw</td>
<td align="right">1098</td>
<td align="right">914</td>
<td align="right">184</td>
<td align="right">372</td>
</tr>
</table>
</blockquote>
<p>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
<em>not</em> support the feature, and a few (such as Solaris)
which provide incomplete support.</p>
<p>The version-naming convention used allows these sample files
to build distinct libraries for ABI 5 and 6. Version names
consist of</p>
<ul>
<li>
<p>configuration name, e.g.,
&ldquo;<code>NCURSESW</code>&rdquo; for the wide-character
libraries</p>
</li>
<li>
<p>ABI version (if not 5)</p>
</li>
<li>
<p>library name for two special cases which have the same
interface across configurations:
&ldquo;<code>TINFO</code>&rdquo; and
&ldquo;<code>TIC</code>&rdquo;</p>
</li>
<li>
<p>release version</p>
</li>
<li>
<p>patch date (for the release version)</p>
</li>
</ul>
<p>For example, running <code>nm -D</code> on the libraries in
the ncurses6 test package shows these symbol-versions:</p>
<blockquote>
<pre class="code-block">
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
</pre>
</blockquote>
<p>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.</p>
<h3><a name="h3-lib-other" id=
"h3-lib-other">Miscellaneous</a></h3>
<p>The new release has several improvements for performance and
building. For instance:</p>
<ul>
<li>
<p>several files in ncurses- and progs-directories were
modified to allow <code>const</code> data used in internal
tables to be put by the linker into the readonly text
segment.</p>
</li>
<li>
<p>various improvements were made to building the Ada95
binding, both in simplifying the generated files as well as
improving the way it uses <code>gnatmake</code></p>
</li>
</ul>
<p>There are also new features in the libraries:</p>
<ul>
<li>added <a href=
"http://invisible-island.net/ncurses/man/curs_util.3x.html#h3-use_tioctl">
use_tioctl</a> function</li>
<li>
<p>added <a href=
"http://invisible-island.net/ncurses/man/curs_opaque.3x.html">
wgetdelay</a> to retrieve _delay member of WINDOW if it
happens to be opaque, e.g., in the pthread configuration.</p>
</li>
<li>
<p>added <a href=
"http://invisible-island.net/ncurses/man/curs_attr.3x.html#h2-PORTABILITY">
A_ITALIC</a> extension.</p>
</li>
<li>
<p>added form library extension <a href=
"http://invisible-island.net/ncurses/man/form_field_opts.3x.html">
O_DYNAMIC_JUSTIFY</a> option which can be used to override
the different treatment of justification for static versus
dynamic fields .</p>
</li>
<li>
<p>rewrote <a href=
"http://invisible-island.net/ncurses/man/curs_util.3x.html#h3-putwin_getwin">
putwin</a> and <a href=
"http://invisible-island.net/ncurses/man/curs_util.3x.html#h3-putwin_getwin">
getwin</a>, making an extended version which is capable of
reading screen-dumps between the wide/normal <em class=
"small-caps">ncurses</em> configurations. These are text
files, except for a <em>magic</em> code at the beginning:</p>
<blockquote>
<pre class="code-block">
0 string \210\210 Screen-dump (ncurses)
</pre>
</blockquote>
</li>
<li>
<p>several changes to mouse support include:</p>
<ul>
<li>added decoder for xterm SGR 1006 mouse mode.</li>
<li>added experimental support for
&ldquo;<code>%u</code>&rdquo; format to terminfo.</li>
<li>improved behavior of wheel-mice for xterm protocol:
noting that there are only button-presses for buttons
&ldquo;4&rdquo; and &ldquo;5&rdquo;, so there is no need to
wait to combine events into double-clicks .</li>
</ul>
</li>
</ul>
<p>There are a few new configure options dealing with library
customization:</p>
<ul>
<li>
<p>add &ldquo;<code>--enable-ext-putwin</code>&rdquo;
configure option to turn on the extended putwin/getwin. By
default, this is enabled for ABI 6 and disabled with ABI
5.</p>
</li>
<li>
<p>add &ldquo;<code>--enable-string-hacks</code>&rdquo;
option to control whether strlcat and strlcpy may be used.
Because <em class="small-caps">ncurses</em> already does the
requisite buffer-limit checks, this feature is mainly of
interest to quiet compiler-warnings on a few systems.</p>
</li>
<li>
<p>add configure option
&ldquo;<code>--with-tparm-arg</code>&rdquo; to allow <a href=
"http://invisible-island.net/ncurses/man/curs_terminfo.3x.html#h3-Formatting-Output">
tparm</a>'s parameters to be something more likely to be the
same size as a pointer, e.g., <code>intptr_t</code> (again,
the default is set for ABI 6).</p>
</li>
</ul>
<h3><a name="h3-programs" id="h3-programs">Program
improvements</a></h3>
<h4><a name="h4-utilities" id="h4-utilities">Utilities</a></h4>
<p>Most of the termcap-related changes based on development of
<a href="http://invisible-island.net/ncurses/tctest.html">tctest
(termcap library checker)</a> are implemented in the tic and
infocmp programs rather than affecting the library. As noted in
the <a href=
"http://invisible-island.net/ncurses/tctest.html#my-better-translation">
discussion</a> of <code>tctest</code>, <em class=
"small-caps">ncurses</em>'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 <em>termcap</em> users are
using <em class="small-caps">ncurses</em> (or NetBSD, with its
own terminfo library) and their programs are actually using
terminfo rather than termcap data.</p>
<p>Still, there are a few. A comment about the translation of the
ASCII <code>NUL</code> character prompted a review:</p>
<ul>
<li>
<p>Both terminfo and termcap store string capabilities as
<code>NUL</code>-terminated strings.</p>
</li>
<li>
<p>In terminfo, a <code>\0</code> in a terminal description
is stored as <code>\200</code>.</p>
</li>
<li>
<p>There are no (known) terminals which would behave
differently when sent <code>\0</code> or
<code>\200</code>.</p>
</li>
<li>
<p>When translating to terminfo format (or displaying a
printable version of an entry using infocmp), <em class=
"small-caps">ncurses</em> shows <code>\200</code> as
<code>\0</code>.</p>
</li>
<li>
<p>It has done this since 1998 (quoting from the NEWS
file):</p>
<blockquote>
<pre class="code-block">
<a href=
"http://invisible-island.net/ncurses/NEWS.html#t980103">980103</a>
...
+ modify _nc_tic_expand() to generate \0 rather than \200.
...
+ correct translation of terminfo "^@", to \200, like \0.
</pre>
</blockquote>
</li>
<li>
<p>However, the <code>_nc_tic_expand</code> function (which
optionally produces terminfo or termcap format) did not
address this special case for termcap. Even the later 4.4BSD
<a href=
"https://svnweb.freebsd.org/base/head/lib/libc/gen/getcap.c?revision=244092&amp;view=markup#l784">
cgetstr</a> interprets a <code>\0</code> literally, ending
<em>that</em> string (rather than using the terminfo
improvement).</p>
</li>
</ul>
<p>As a result of the review, several improvements were made to
<em class="small-caps">ncurses</em> translation to/from termcap
format &mdash; 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:</p>
<ul>
<li>
<p>the &ldquo;<code>-0</code>&rdquo; option generates
termcap/terminfo source on a single line.</p>
</li>
<li>
<p>the &ldquo;<code>-K</code>&rdquo; option provides stricter
BSD-compatibility for termcap output.</p>
</li>
</ul>
<p>Other user-visible improvements and new features include:</p>
<ul>
<li>
<p>added &ldquo;<code>-D</code>&rdquo; option to tic and
infocmp, to show the database locations that it could
use.</p>
</li>
<li>
<p>added &ldquo;<code>-s</code>&rdquo; option to toe, to sort
its output.</p>
</li>
<li>
<p>extended &ldquo;<code>-c</code>&rdquo; and
&ldquo;<code>-n</code>&rdquo; options of infocmp to allow
comparing more than two entries.</p>
</li>
<li>
<p>modified toe's report when &ldquo;<code>-a</code>&rdquo;
and &ldquo;<code>-s</code>&rdquo; options are combined, to
add a column showing which entries belong to a given
database.</p>
</li>
<li>
<p>modified the clear program to take into account the
&ldquo;<code>E3</code>&rdquo; extended capability to clear
the terminal's scrollback buffer.</p>
</li>
</ul>
<h4><a name="h4-examples" id="h4-examples">Examples</a></h4>
<p>Along with the library and utilities, many improvements were
made to the <a href=
"http://invisible-island.net/ncurses/ncurses-examples.html">ncurses-examples</a>.
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).</p>
<p>These changes were made to verify compatibility or compare
performance of <em class="small-caps">ncurses</em>:</p>
<ul>
<li>
<p>made workarounds for compiling test-programs with NetBSD
curses, though it lacks some common functions such as
<a href="http://invisible-island.net/ncurses/man/curs_util.3x.html#h3-use_env">
use_env</a>.</p>
</li>
<li>
<p>added dots_termcap test-program</p>
</li>
<li>
<p>added dots_curses test-program, for comparison with the
low-level examples.</p>
</li>
<li>
<p>added test_setupterm test-proram to demonstrate
normal/error returns from the setupterm and restartterm
functions.</p>
</li>
<li>
<p>added &ldquo;<code>-d</code>&rdquo;,
&ldquo;<code>-e</code>&rdquo; and
&ldquo;<code>-q</code>&rdquo; options to the demo_terminfo
and demo_termcap test-programs.</p>
</li>
<li>
<p>added &ldquo;<code>-y</code>&rdquo; option to demo_termcap
and test/demo_terminfo test-programs to demonstrate behavior
with/without extended capabilities.</p>
</li>
<li>
<p>modified demo_termcap and demo_terminfo test-programs to
make their options more directly comparable, and add
&ldquo;<code>-i</code>&rdquo; option to specify a terminal
description filename to parse for names to lookup.</p>
</li>
<li>
<p>rewrote the tests for <a href=
"http://invisible-island.net/ncurses/man/curs_window.3x.html#h3-derwin">
mvderwin</a> and test for recursive <a href=
"http://invisible-island.net/ncurses/man/curs_window.3x.html#h3-mvwin">
mvwin</a> in the movewindow test-program.</p>
</li>
</ul>
<p>These changes were made to help with the MinGW port:</p>
<ul>
<li>
<p>added test-screens to the ncurses test-program to show
256-characters at a time, to help with MinGW port.</p>
</li>
<li>
<p>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.</p>
</li>
<li>
<p>added &ldquo;<code>-s</code>&rdquo; 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.</p>
</li>
</ul>
<p>These changes were made to verify new extensions in <em class=
"small-caps">ncurses</em>:</p>
<ul>
<li>
<p>added <a href=
"http://invisible-island.net/ncurses/man/form_driver.3x.html#h3-form_driver_w">
form_driver_w</a> entrypoint to wide-character forms library,
as well as form_driver_w test-program.</p>
</li>
<li>
<p>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.</p>
</li>
<li>
<p>modified ncurses test-program, adding
&ldquo;<code>-E</code>&rdquo; and
&ldquo;<code>-T</code>&rdquo; options to demonstrate use_env
versus use_tioctl.</p>
</li>
<li>
<p>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.</p>
</li>
<li>
<p>modified the ncurses test-program to also show position
reports in 'a' test.</p>
</li>
</ul>
<p>These changes were made to make the examples more useful:</p>
<ul>
<li>
<p>added scripts for building dpkg and rpm test-packages</p>
</li>
<li>
<p>modified the hanoi test-program to show the minimum number
of moves possible for the given number of tiles.</p>
</li>
<li>
<p>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.</p>
</li>
</ul>
<h3><a name="h3-database" id="h3-database">Terminal
database</a></h3>
<p>This release provides improvements to tic's
&ldquo;<code>-c</code>&rdquo; checking option, which was used for
example to</p>
<ul>
<li>
<p>make <code>sgr</code> in several entries agree with other
caps.</p>
</li>
<li>
<p>correct padding in some entries where earlier versions had
miscounted the number of octal digits.</p>
</li>
</ul>
<p>There are several new terminal descriptions:</p>
<ul>
<li><a href=
"http://invisible-island.net/ncurses/terminfo.src.html#toc-_M_L_T_E_R_M">
mlterm</a> is now aliased to mlterm3</li>
<li><a href=
"http://invisible-island.net/ncurses/terminfo.src.html#tic-nsterm">
nsterm</a> is now derived from nsterm-256color</li>
<li><a href=
"http://invisible-island.net/ncurses/terminfo.src.html#tic-putty-sco">
putty-sco</a></li>
<li><a href=
"http://invisible-island.net/ncurses/terminfo.src.html#tic-teken">
teken</a> is FreeBSD's "xterm" console.</li>
<li><a href=
"http://invisible-island.net/ncurses/terminfo.src.html#toc-_T_E_R_M_I_N_A_T_O_R">
terminator</a></li>
<li><a href=
"http://invisible-island.net/ncurses/terminfo.src.html#toc-_T_E_R_M_I_N_O_L_O_G_Y">
terminology</a></li>
<li><a href=
"http://invisible-island.net/ncurses/terminfo.src.html#tic-tmux">
tmux</a> is derived from screen.</li>
<li>several screen.XXX entries support the respective
variations for 256 colors.</li>
<li><a href=
"http://invisible-island.net/ncurses/terminfo.src.html#toc-_S_I_M_P_L_E_T_E_R_M">
simpleterm</a> is now 0.5</li>
<li><a href=
"http://invisible-island.net/ncurses/terminfo.src.html#tic-vte">
vte</a> is aliased to vte-2012</li>
<li><a href=
"http://invisible-island.net/ncurses/terminfo.src.html#tic-vt520ansi">
vt520ansi</a></li>
</ul>
<p>A few entries use extensions (user-defined terminal
capabilities):</p>
<ul>
<li>
<p><code>E3</code>, used in linux, putty and xterm-basic is
tested in the <a href=
"http://aerie.jexium-island.net/ncurses/man/clear.1.html">clear</a>
program to erase a terminal's scrollback.</p>
</li>
<li>
<p><code>TS</code> is used in the <a href=
"http://invisible-island.net/ncurses/terminfo.src.html#tic-xterm_sl">
xterm+sl</a> building block to help deprecate the misuse of
<code>tsl</code> for xterm's title-string.</p>
</li>
<li>
<p><code>XT</code> 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.</p>
</li>
<li>
<p><code>xm</code> is used in examples <a href=
"http://invisible-island.net/ncurses/terminfo.src.html#tic-xterm-1005">
xterm-1005</a> and <a href=
"http://invisible-island.net/ncurses/terminfo.src.html#tic-xterm-1006">
xterm-1006</a> to illustrate a way to make mouse handling
more general</p>
</li>
</ul>
<p>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
<code>A_ITALIC</code> extension.</p>
<ul>
<li>konsole, mlterm3 (italics)</li>
<li>nsterm (dim)</li>
<li>screen (dim)</li>
<li>vte (dim, italics)</li>
<li>xterm (dim, italics)</li>
</ul>
<h3><a name="h3-documentation" id=
"h3-documentation">Documentation</a></h3>
<p>As usual, this release</p>
<ul>
<li>
<p>improves documentation by describing new features,</p>
</li>
<li>
<p>attempts to improve the description of features which
users have found confusing</p>
</li>
<li>
<p>fills in overlooked descriptions of features which were
described in the <a href=
"http://invisible-island.net/ncurses/NEWS.html">NEWS</a> file
but treated sketchily in manual pages.</p>
</li>
</ul>
<p>In addition, the mechanism for producing HTML versions of the
documentation has been improved:</p>
<ul>
<li>
<p>use an improved version of <a href=
"http://invisible-island.net/scripts/man2html.html">man2html</a>
to generate html manpages.</p>
</li>
<li>
<p>regenerated <a href=
"http://invisible-island.net/ncurses/NCURSES-Programming-HOWTO.html">
NCURSES-Programming-HOWTO.html</a> to fix some of the broken
html emitted by docbook.</p>
</li>
</ul>
<h3><a name="h3-bug-fixes" id="h3-bug-fixes">Interesting
bug-fixes</a></h3>
<ul>
<li>
<p>Ada95 binding:</p>
<ul>
<li>
<p>modify makefile rules to ensure that the PIC option is
not used when building a static library</p>
</li>
<li>
<p>make Ada95 build-fix for big-endian architectures such
as sparc. This undoes one of the fixes from <a href=
"http://invisible-island.net/ncurses/NEWS.html#t20110319">
20110319</a>, which added an
&ldquo;<code>Unused</code>&rdquo; member to
representation clauses, replacing that with pragmas to
suppress warnings about unused bits.</p>
</li>
</ul>
</li>
<li>
<p>Color and attributes:</p>
<ul>
<li>
<p>parenthesize parameter of <code>COLOR_PAIR</code> and
<code>PAIR_NUMBER</code> in curses.h in case it happens
to be a comma-expression.</p>
</li>
<li>
<p>improve <a href=
"http://invisible-island.net/ncurses/NEWS.html#t20021221">
20021221</a> workaround for broken acs, handling a case
where that ACS_<em>xxx</em> character is not in the
<code>acsc</code> string but there is a known
wide-character which can be used.</p>
</li>
<li>
<p>modify <a href=
"http://invisible-island.net/ncurses/man/curs_color.3x.html#h3-Routine-Descriptions">
init_pair</a> to accept -1's for color value after
<a href=
"http://invisible-island.net/ncurses/man/default_colors.3x.html">
assume_default_colors</a> has been called.</p>
</li>
<li>
<p>add a check in <a href=
"http://invisible-island.net/ncurses/man/curs_color.3x.html#h3-Routine-Descriptions">
start_color</a> to limit color-pairs to 256 when extended
colors are not supported.</p>
</li>
</ul>
</li>
<li>
<p>Resizing the screen:</p>
<ul>
<li>
<p>propagate error-returns from wresize, i.e., the
internal increase_size and decrease_size functions
through <a href=
"http://invisible-island.net/ncurses/man/resizeterm.3x.html">
resize_term</a>.</p>
</li>
<li>
<p>add check for zero/negative dimensions for
<code>resizeterm</code> and <code>resize_term</code>.</p>
</li>
<li>
<p>modify <code>resizeterm</code> to always push a
<code>KEY_RESIZE</code> onto the fifo, even if screensize
is unchanged. Modify library to push a
<code>KEY_RESIZE</code> if there was a SIGWINCH, even if
it does not call <code>resizeterm</code>). These changes
eliminate the case where a SIGWINCH is received, but ERR
is returned from <code>wgetch</code> or
<code>wgetnstr</code> because the screen dimensions did
not change.</p>
</li>
</ul>
</li>
<li>
<p>Low-level interfaces</p>
<ul>
<li>
<p>fix an old bug in the termcap emulation;
&ldquo;<code>%i</code>&rdquo; was ignored in
<code>tparm</code> because the parameters to be
incremented were already on the internal stack.</p>
</li>
<li>
<p>change &ldquo;<code>%l</code>&rdquo; behavior in tparm
to push the string length onto the stack rather than
saving the formatted length into the output buffer.</p>
</li>
<li>
<p>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 <a href=
"http://invisible-island.net/ncurses/NEWS.html#t980725">980725</a>).</p>
</li>
</ul>
</li>
<li>High-level interfaces
<ul>
<li>
<p>modify internal recursion in <code>wgetch</code> which
handles cooked mode to check if the call to
<code>wgetnstr</code> returned an error. This can happen
when both <code>nocbreak</code> and <code>nodelay</code>
are set, for instance (see note for <a href=
"http://invisible-island.net/ncurses/NEWS.html#t960418">960418</a>).</p>
</li>
<li>
<p>add a check in internal function
<code>waddch_nosync</code> to ensure that tab characters
are treated as control characters; some broken locales
claim they are printable.</p>
</li>
<li>
<p>modify menu library to ensure that a menu's top-row is
adjusted as needed to ensure that the current item is on
the screen</p>
</li>
<li>
<p>fix special case where double-width character
overwrites a single- width character in the first
column.</p>
</li>
</ul>
</li>
</ul>
<h3><a name="h3-config-config" id=
"h3-config-config">Configuration changes</a></h3>
<h4><a name="h4-config-major" id="h4-config-major">Major
changes</a></h4>
<p>The <em class="small-caps">ncurses</em> 6.0 configure script
makes changes to the <em>default</em> value of several configure
options, depending on the <code>--with-abi-version</code> option
(i.e., whether its value is &ldquo;5&rdquo; or
&ldquo;6&rdquo;):</p>
<dl>
<dt><code>--enable-const</code></dt>
<dd>
<p>Feature introduced in <a href=
"http://invisible-island.net/ncurses/NEWS.html#t970405">970405</a>
supports the use of <code>const</code> where X/Open Curses
should have, but did not. NetBSD curses does something
similar with <code>const</code>.</p>
</dd>
<dt><code>--enable-ext-colors</code></dt>
<dd>
<p>Extends the <code>cchar_t</code> structure to allow more
than 16 colors to be encoded. This applies only to the
wide-character (<code>--enable-widec</code>)
configuration.</p>
</dd>
<dt><code>--enable-ext-mouse</code></dt>
<dd>
<p>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.</p>
</dd>
<dt><code>--enable-ext-putwin</code></dt>
<dd>
<p>Modifies the file-format written by <code>putwin</code> to
use printable text rather than binary files, allowing
<code>getwin</code> to read screen dumps written by
differently-configured ncurses libraries. The extended
<code>getwin</code> can still read binary screen dumps from
the <em>same</em> configuration of ncurses. This does not
change the ABI (the binary interface seen by calling
applications).</p>
</dd>
<dt><code>--enable-interop</code></dt>
<dd>
<p>Modifies the <code>FIELDTYPE</code> structure used for the
form library to make it more generic.</p>
</dd>
<dt><code>--enable-lp64</code></dt>
<dd>
<p>Allows an application to define <code>_LP64</code> to
declare <code>chtype</code> and <code>mmask_t</code> as
simply &ldquo;<code>unsigned</code>&rdquo; rather than the
configured types using the <code>--with-chtype</code> and
<code>--with-mmask_t</code> options.</p>
</dd>
<dt><code>--enable-sp-funcs</code></dt>
<dd>
<p>Compile-in support for extended functions which accept a
SCREEN pointer, reducing the need for juggling the global SP
value with <a href=
"http://invisible-island.net/ncurses/man/curs_initscr.3x.html#h3-set_term">
set_term</a> and <a href=
"http://invisible-island.net/ncurses/man/curs_initscr.3x.html#h3-delscreen">
delscreen</a>.</p>
</dd>
<dt><code>--with-chtype=uint32_t</code></dt>
<dd>
<p>Makes <code>chtype</code> explicitly a 32-bit unsigned
value.</p>
</dd>
<dt><code>--with-mmask_t=uint32_t</code></dt>
<dd>
<p>Makes <code>mmask_t</code> explicitly a 32-bit unsigned
value.</p>
</dd>
<dt><code>--with-tparm-arg=intptr_t</code></dt>
<dd>
<p>X/Open Curses declares <a href=
"http://invisible-island.net/ncurses/man/curs_terminfo.3x.html#h3-Formatting-Output">
tparm</a> using <code>long</code> for each of the parameters
aside from the formatting string, presuming that
<code>long</code> and <code>char*</code> are the same size.
This configure option uses <code>intptr_t</code> which
provides a better guarantee of the sizes.</p>
</dd>
</dl>
<p>The configure script no longer checks for antique compilers;
<code>c89</code> 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 <em class=
"small-caps">ncurses</em> 6.0 with any of the current (or not so
current) C compilers available in 2015.</p>
<p>The configure script, by the way, makes changes which do not
work with systems whose <code>/bin/sh</code> is non-POSIX. This
mainly affects Solaris (the other vendor <em class=
"small-caps">unix</em> systems have followed the POSIX guidelines
for the past twenty years). If you must build on Solaris, its
<a href=
"http://docs.oracle.com/cd/E19253-01/html/817-0552/fhkpy.html">xpg4</a>
binaries suffice, e.g.,</p>
<blockquote class="code-block">
<!--{{atr2html-->
<p style="font-family: monospace; font-size: 10pt;">
<font color="#800000">#!/bin/sh</font><br>
<font color="#008080">WHAT</font>=<strong><em><font color=
"#800000">`</font></em></strong>hostname|sed&nbsp;-e&nbsp;<font color="#800080">'s/\..*//'</font><strong><em><font color="#800000">`</font></em></strong><br>
<font color="#008080">OUT</font>=configure.out<br>
<strong><font color=
"#000080">cat</font></strong>&nbsp;&gt;&gt;<font color=
"#008080">$OUT</font>&nbsp;<font color=
"#800080">&lt;&lt;EOF/</font><font color="#800080"><br>
**&nbsp;</font><strong><em><font color=
"#800000">`</font></em></strong>date<strong><em><font color=
"#800000">`</font></em></strong><font color="#800080"><br>
**&nbsp;node:&nbsp;</font><font color=
"#008080">$WHAT</font><font color="#800080"><br>
**&nbsp;user:&nbsp;</font><strong><em><font color=
"#800000">`</font></em></strong>id<strong><em><font color=
"#800000">`</font></em></strong><font color="#800080"><br>
**&nbsp;conf:&nbsp;$*<br>
EOF/</font><br>
&nbsp;<br>
<font color="#008080">SHELL</font>=/bin/sh<br>
<strong><font color=
"#000080">if</font></strong>&nbsp;<strong><font color=
"#000080">test</font></strong>&nbsp;-f&nbsp;/usr/xpg4/bin/sh<br>
<strong><font color="#000080">then</font></strong><br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font color=
"#008080">CONFIG_SHELL</font>=/usr/xpg4/bin/sh<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<strong><font color="#000080">export</font></strong>&nbsp;CONFIG_SHELL<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<font color=
"#008080">SHELL</font>=<font color=
"#008080">$CONFIG_SHELL</font><br>
<strong><font color="#000080">fi</font></strong><br>
&nbsp;<br>
rm&nbsp;-f&nbsp;config.status&nbsp;config.cache<br>
<font color="#008080">TOP</font>=<font color=
"#008080">$HOME</font>/<font color="#008080">$WHAT</font><br>
<font color=
"#008080">$SHELL</font>&nbsp;./configure&nbsp;--verbose&nbsp;\<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;--disable-echo&nbsp;\<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;--disable-overwrite&nbsp;\<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;--enable-warnings&nbsp;\<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;--with-warnings&nbsp;\<br>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;--prefix=<font color="#008080">$TOP</font>&nbsp;<font color="#008080">$*</font>&nbsp;<strong><font color="#008080">2</font></strong>&gt;&amp;<strong><font color="#008080">1</font></strong>&nbsp;|&nbsp;tee&nbsp;-a&nbsp;<font color="#008080">$OUT</font><br>
<!--atr2html}}--></p>
</blockquote>
<p>Other major changes to the configure script include:</p>
<ul>
<li>
<p>ABI 6 is now the default, intending that the existing ABI
5 should build as before using the
&ldquo;<code>--with-abi-version=5</code>&rdquo; option.</p>
</li>
<li>
<p>added <code>--with-extra-suffix</code> option to help with
installing nonconflicting ncurses6 packages, e.g., avoiding
header- and library-conflicts.</p>
<p><strong>NOTE:</strong> as a side-effect, this renames</p>
<blockquote>
<p><code>adacurses-config</code> to
<code>adacurses5-config</code> and<br>
<code>adacursesw-config</code> to
<code>adacursesw5-config</code></p>
</blockquote>
</li>
<li>
<p>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.</p>
</li>
<li>
<p>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.</p>
</li>
</ul>
<h4><a name="h4-config-options" id=
"h4-config-options">Configuration options</a></h4>
<p>There are several new (or extended) configure options:</p>
<dl>
<dt><code>--disable-db-install</code></dt>
<dd>
<p>Do not install the terminal database. This is used to omit
features for packages, as done with
<code>--without-progs</code>. The option simplifies building
cross-compile support packages.</p>
</dd>
<dt><code>--disable-gnat-projects</code></dt>
<dd>
<p>This option is used for regression testing</p>
</dd>
<dt><code>--disable-lib-suffixes</code></dt>
<dd>
<p>Suppress the &ldquo;w&rdquo;, &ldquo;t&rdquo; or
&ldquo;tw&rdquo; suffixes which normally would be added to
the library names for the <code>--enable-widec</code> and
<code>--with-pthread</code> options.</p>
</dd>
<dt><code>--with-cxx-shared</code></dt>
<dd>
<p>When <code>--with-shared</code> 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 limitations.</p>
</dd>
<dt><code>--with-hashed-db</code></dt>
<dd>
<p>Extended this configure option to simplify building with
different versions of Berkeley database using FreeBSD
ports.</p>
</dd>
<dt><code>--with-pc-suffix</code></dt>
<dd>
<p>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.</p>
</dd>
<dt><code>--with-xterm-kbs</code></dt>
<dd>
<p>Configure xterm's terminfo entries to use either BS
(<code>^H</code>, i.e., ASCII backspace) or DEL
(<code>^?</code>, or 127).</p>
</dd>
</dl>
<h3><a name="h3-portability" id=
"h3-portability">Portability</a></h3>
<h4><a name="h4-port-mingw" id="h4-port-mingw">MinGW</a></h4>
<p>Most of the portability-related work since <a href=
"http://invisible-island.net/ncurses/announce-5.9.html"><em class="small-caps">
ncurses</em> 5.9</a> extended and improved the MinGW port
introduced in <a href=
"http://invisible-island.net/ncurses/announce-5.8.html"><em class="small-caps">
ncurses</em> 5.8</a>.</p>
<p>The MinGW port can be readily cross-compiled:</p>
<ul>
<li>
<p>modified configure script to allow creating dll's for
MinGW when cross-compiling.</p>
</li>
<li>
<p>enforced Windows-style path-separator if
cross-compiling,</p>
</li>
<li>
<p>added scripts for test-builds of cross-compiled packages
for ncurses6 to MinGW.</p>
</li>
<li>
<p>added pc-files to the MinGW cross-compiling
test-packages.</p>
</li>
<li>
<p>added script for building test-packages of binaries
cross-compiled to MinGW using NSIS.</p>
</li>
<li>
<p>added <code>nc_mingw.h</code> to installed headers for
MinGW port; this is needed for cross-compiling <a href=
"http://invisible-island.net/ncurses/ncurses-examples.html">ncurses-examples</a>.</p>
</li>
<li>
<p>added test-packages for cross-compiling ncurses-examples
using the MinGW test-packages.</p>
</li>
</ul>
<p>The MinGW-specific Windows driver accounts for several
changes:</p>
<ul>
<li>
<p>wide-character display is made usable by replacing MinGW's
non-working <code>wcrtomb</code> and <code>wctomb</code>
functions.</p>
</li>
<li>
<p>implemented some display features: <a href=
"http://invisible-island.net/ncurses/man/curs_beep.3x.html">beep</a>,
<a href=
"http://invisible-island.net/ncurses/man/curs_beep.3x.html">flash</a>,
<a href=
"http://invisible-island.net/ncurses/man/curs_kernel.3x.html#h3-curs_set">
curs_set</a>.</p>
</li>
<li>
<p>the driver handles repainting on endwin/refresh
combination.</p>
</li>
<li>
<p>modified treatment of <code>TERM</code> variable for MinGW
port to allow explicit use of the Windows console driver by
checking if <code>$TERM</code> is set to
&ldquo;<code>#win32console</code>&rdquo; or an abbreviation
of that.</p>
</li>
<li>
<p>the Windows driver also matches the special
<code>TERM</code> value &ldquo;unknown&rdquo;</p>
</li>
<li>
<p>the driver now returns characters for special keys, (like
<code>ansi.sys</code> does), when keypad mode is off, rather
than returning nothing at all.</p>
</li>
<li>
<p>the driver checks a new environment variable <a href=
"http://invisible-island.net/ncurses/man/ncurses.3x.html#h3-NCURSES_CONSOLE2">
NCURSES_CONSOLE2</a> to optionally work around a deficiency
in <code>Console2</code> (and its descendent
<code>ConsoleZ</code>) which hang when an application creates
a console buffer.</p>
</li>
</ul>
<p>Finally, there are other improvements:</p>
<ul>
<li>
<p>MinGW is one of the configurations where <em class=
"small-caps">ncurses</em> installs by default into /usr</p>
</li>
<li>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.</li>
<li>
<p>extend Windows support to work with MSYS2;</p>
<ul>
<li>
<p>this works with a scenario where there is an
ANSI-escape handler such as <code>ansicon</code> running
in the console window.</p>
</li>
<li>wrap <code>isatty</code> calls with a macro, provide a
corresponding set of support routines to address
differences between MinGW and MSYS2.</li>
</ul>
</li>
<li>
<p>ensure <code>WINVER</code> is defined in makefiles rather
than using headers.</p>
</li>
<li>
<p>add check for the <code>gnatprep</code>
&ldquo;<code>-T</code>&rdquo; option.</p>
</li>
<li>
<p>work around a bug introduced by <a href=
"http://stackoverflow.com/questions/20877689/gcc-4-8-1-minggw-d-option-does-not-work-as-usual">
gcc 4.8.1</a> in MinGW which breaks "trace" feature.</p>
</li>
<li>
<p>add a driver-name method to each of the drivers.</p>
</li>
</ul>
<h4><a name="h4-port-systems" id="h4-port-systems">Other
ports</a></h4>
<p>These changes affect certain platforms (ports):</p>
<ul>
<li>
<p>the configure script knows how to build shared libraries
with DragonFlyBSD and Interix.</p>
</li>
<li>
<p>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:</p>
<ul>
<li>
<p>the shared-library suffix for AIX 5 and 6 is now
".so"</p>
</li>
<li>
<p>the <code>-brtl</code> option is used with AIX 5-7; it
is needed to link with the shared libraries.</p>
</li>
</ul>
</li>
<li>
<p>the configure <code>--enable-pc-files</code> option takes
into account the <a href=
"http://linux.die.net/man/1/pkg-config"><code>PKG_CONFIG_PATH</code></a>
variable.</p>
</li>
<li>
<p>the configure option <code>--with-pkg-config-libdir</code>
provides control over the actual directory into which
pc-files are installed.</p>
</li>
<li>
<p>the build scripts add explicit -ltinfo, etc., to the
generated ".pc" file when <code>ld</code> option
&ldquo;<code>--as-needed</code>&rdquo; is used, or when
ncurses and tinfo are installed without using rpath.</p>
</li>
<li>
<p>the configure script disallows conflicting options
&ldquo;<code>--with-termlib</code>&rdquo; and
&ldquo;<code>--enable-term-driver</code>&rdquo;.</p>
</li>
<li>
<p>the check for missing c++ compiler to work when no error
is reported, and no variables set is improved (see note for
<a href=
"http://invisible-island.net/ncurses/NEWS.html#t20021206">20021206</a>).</p>
</li>
<li>
<p>the misc/gen_edit.sh script selects a "linux" entry which
works with the current kernel rather than assuming it is
always "linux3.0"</p>
</li>
<li>
<p>the test/configure script makes it simpler to override
names of curses-related libraries, to help with linking with
pdcurses in MinGW environment.</p>
</li>
<li>
<p>the configure-script/ifdef's allow the BSD OLD_TTY feature
to be suppressed if the type of <code>ospeed</code> is
configured using the option <code>--with-ospeed</code> to not
be a <code>short</code>. By default, it is a
<code>short</code> for termcap-compatibility.</p>
</li>
<li>
<p>the MKlib_gen.sh script works around a recent change in
gcc 5 (released <a href=
"https://gcc.gnu.org/gcc-5/">mid-2015</a>) which essentially
emits multiple <code>#line</code> statements for the same
position in a file.</p>
</li>
<li>
<p>the configure script works with Minix3.2 (see <a href=
"http://invisible-island.net/autoconf/portability-test.html">note</a>
on portability)</p>
</li>
<li>
<p>OS/2 redux:</p>
<ul>
<li>
<p>the configure script supports OS/2 kLIBC.</p>
</li>
<li>
<p>the <code>--with-lib-prefix</code> option allows
configuring for old/new flavors of OS/2 EMX.</p>
</li>
</ul>
</li>
<li>
<p>improved configure-script checks for
<code>_XOPEN_SOURCE</code>:</p>
<ul>
<li>
<p>the definition works starting with Solaris 10.</p>
</li>
<li>
<p>the definition is suppressed for IRIX64, since its
header files have a conflict versus
<code>_SGI_SOURCE</code>.</p>
</li>
</ul>
</li>
</ul>
<hr>
<h2><a name="h2-features" id="h2-features">Features of <em class=
"small-caps">ncurses</em></a></h2>
<p>The <em class="small-caps">ncurses</em> package is fully
upward-compatible with SVr4 (System V Release 4) curses:</p>
<ul>
<li>
<p>All of the SVr4 calls have been implemented (and are
documented).</p>
</li>
<li>
<p><em class="small-caps">ncurses</em> 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.</p>
</li>
<li>
<p><em class="small-caps">ncurses</em> provides these SVr4
add-on libraries (not part of X/Open Curses):</p>
<ul>
<li>
<p>the panels library, supporting a stack of windows with
backing store.</p>
</li>
<li>
<p>the menus library, supporting a uniform but flexible
interface for menu programming.</p>
</li>
<li>
<p>the form library, supporting data collection through
on-screen forms.</p>
</li>
</ul>
</li>
<li>
<p><em class="small-caps">ncurses</em>'s terminal database is
fully compatible with that used by SVr4 curses.</p>
<ul>
<li><em class="small-caps">ncurses</em> supports
user-defined capabilities which it can see, but which are
hidden from SVr4 curses applications using the
<em>same</em> terminal database.</li>
<li>
<p>It can be optionally configured to match the format
used in related systems such as AIX and Tru64.</p>
</li>
<li>
<p>Alternatively, <em class="small-caps">ncurses</em> can
be configured to use hashed databases rather than the
directory of files used by SVr4 curses.</p>
</li>
</ul>
</li>
<li>
<p>The <em class="small-caps">ncurses</em> utilities have
options to allow you to filter terminfo entries for use with
less capable <em>curses</em>/<em>terminfo</em> versions such
as the HP/UX and AIX ports.</p>
</li>
</ul>
<p>The <em class="small-caps">ncurses</em> package also has many
useful extensions over SVr4:</p>
<ul>
<li>
<p>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).</p>
</li>
<li>
<p>Unlike SVr3 curses, <em class="small-caps">ncurses</em>
can write to the rightmost-bottommost corner of the screen if
your terminal has an insert-character capability.</p>
</li>
<li>
<p>Ada95 and C++ bindings.</p>
</li>
<li>
<p>Support for mouse event reporting with X Window xterm and
FreeBSD and OS/2 console windows.</p>
</li>
<li>
<p>Extended mouse support via Alessandro Rubini's gpm
package.</p>
</li>
<li>
<p>The function <code>wresize</code> allows you to resize
windows, preserving their data.</p>
</li>
<li>
<p>The function <code>use_default_colors</code> allows you to
use the terminal's default colors for the default color pair,
achieving the effect of transparent colors.</p>
</li>
<li>
<p>The functions <code>keyok</code> and
<code>define_key</code> allow you to better control the use
of function keys, e.g., disabling the <em class=
"small-caps">ncurses</em> KEY_MOUSE, or by defining more than
one control sequence to map to a given key code.</p>
</li>
<li>
<p>Support for 256-color terminals, such as modern xterm.</p>
</li>
<li>
<p>Support for 16-color terminals, such as <em>aixterm</em>
and <em>modern xterm</em>.</p>
</li>
<li>
<p>Better cursor-movement optimization. The package now
features a cursor-local-movement computation more efficient
than either BSD's or System V's.</p>
</li>
<li>
<p>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
<code>quickch</code> routine.</p>
</li>
<li>
<p>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.</p>
</li>
<li>
<p>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).</p>
</li>
<li>
<p>The <a href=
"http://invisible-island.net/ncurses/man/tic.1m.html">tic</a>/<a href="http://invisible-island.net/ncurses/man/captoinfo.1m.html">captoinfo</a>
utility provided with <em class="small-caps">ncurses</em> has
the ability to translate many termcaps from the XENIX, IBM
and AT&amp;T extension sets.</p>
</li>
<li>
<p>A BSD-like <a href=
"http://invisible-island.net/ncurses/man/tset.1.html">tset</a>
utility is provided.</p>
</li>
<li>
<p>The <em class="small-caps">ncurses</em> 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.</p>
</li>
<li>
<p>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.)</p>
</li>
<li>
<p>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.</p>
</li>
<li>
<p>The table-of-entries utility <a href=
"http://invisible-island.net/ncurses/man/toe.1m.html">toe</a>
makes it easy for users to see exactly what terminal types
are available on the system.</p>
</li>
<li>
<p>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 <code>#undef</code>.</p>
</li>
<li>
<p>Extensive documentation is provided (see the <em><a href=
"http://invisible-island.net/ncurses/ncurses.faq.html#additional_reading">
Additional Reading</a></em> section of the <em><a href=
"http://invisible-island.net/ncurses/ncurses.faq.html"><em class="small-caps">
ncurses</em> FAQ</a></em> for online documentation).</p>
</li>
</ul>
<h2><a name="h2-who-uses" id="h2-who-uses">Applications using
<em class="small-caps">ncurses</em></a></h2>
<p>The <em class="small-caps">ncurses</em> distribution includes
a selection of test programs (including a few games). These are
available separately as <a href=
"http://invisible-island.net/ncurses/ncurses-examples.html">ncurses-examples</a></p>
<p>The ncurses library has been tested with a wide variety of
applications including:</p>
<blockquote>
<dl>
<dt>cdk</dt>
<dd>
<p>Curses Development Kit</p>
<p><a href=
"http://invisible-island.net/cdk/">http://invisible-island.net/cdk/</a><br>
</p>
</dd>
<dt>ded</dt>
<dd>
<p>directory-editor</p>
<p><a href=
"http://invisible-island.net/ded/">http://invisible-island.net/ded/</a></p>
</dd>
<dt>dialog</dt>
<dd>
<p>the underlying application used in Slackware's setup,
and the basis for similar install/configure applications on
many systems.</p>
<p><a href=
"http://invisible-island.net/dialog/">http://invisible-island.net/dialog/</a></p>
</dd>
<dt>lynx</dt>
<dd>
<p>the text WWW browser</p>
<p><a href=
"http://lynx.isc.org/">http://lynx.isc.org/</a></p>
</dd>
<dt>Midnight Commander</dt>
<dd>
<p>file manager</p>
<p><a href=
"http://www.midnight-commander.org/">http://www.midnight-commander.org/</a></p>
</dd>
<dt>mutt</dt>
<dd>
<p>mail utility</p>
<p><a href=
"http://www.mutt.org/">http://www.mutt.org/</a></p>
</dd>
<dt>ncftp</dt>
<dd>
<p>file-transfer utility</p>
<p><a href=
"http://www.ncftp.com/">http://www.ncftp.com/</a></p>
</dd>
<dt>nvi</dt>
<dd>
<p>New vi uses ncurses.</p>
<p><a href=
"https://sites.google.com/a/bostic.com/keithbostic/nvi">https://sites.google.com/a/bostic.com/keithbostic/nvi</a><br>
</p>
</dd>
<dt>tin</dt>
<dd>
<p>newsreader, supporting color, MIME</p>
<p><a href=
"http://www.tin.org/">http://www.tin.org/</a></p>
</dd>
</dl>
</blockquote>
<p>as well as some that use <em class="small-caps">ncurses</em>
for the terminfo support alone:</p>
<blockquote>
<dl>
<dt>minicom</dt>
<dd>
<p>terminal emulator for serial modem connections</p>
<p><a href=
"http://alioth.debian.org/projects/minicom/">http://alioth.debian.org/projects/minicom/</a></p>
</dd>
<dt>mosh</dt>
<dd>
<p>a replacement for <code>ssh</code>.</p>
<p><a href=
"https://mosh.mit.edu/">https://mosh.mit.edu/</a></p>
</dd>
<dt>tack</dt>
<dd>
<p>terminfo action checker</p>
<p><a href=
"http://invisible-island.net/ncurses/tack.html">http://invisible-island.net/ncurses/tack.html</a></p>
</dd>
<dt>tmux</dt>
<dd>
<p>terminal multiplexor</p>
<p><a href=
"http://tmux.github.io/">http://tmux.github.io/</a></p>
</dd>
<dt>vile</dt>
<dd>
<p>vi-like-emacs may be built to use the terminfo, termcap
or curses interfaces.</p>
<p><a href=
"http://invisible-island.net/vile/">http://invisible-island.net/vile/</a></p>
</dd>
</dl>
</blockquote>
<p>and finally, those which use only the termcap interface:</p>
<blockquote>
<dl>
<dt>emacs</dt>
<dd>
<p>text editor</p>
<p><a href=
"http://www.gnu.org/software/emacs/">http://www.gnu.org/software/emacs/</a></p>
</dd>
<dt>screen</dt>
<dd>
<p>terminal multiplexor</p>
<p><a href=
"http://www.gnu.org/software/screen/">http://www.gnu.org/software/screen/</a></p>
</dd>
<dt>vim</dt>
<dd>
<p>text editor</p>
<p><a href=
"http://www.vim.org/">http://www.vim.org/</a></p>
</dd>
</dl>
</blockquote>
<h2><a name="h2-development" id="h2-development">Development
activities</a></h2>
<p>Zeyd Ben-Halim started <em class="small-caps">ncurses</em>
from a previous package pcurses, written by Pavel Curtis. Eric S.
Raymond continued development. J&uuml;rgen Pfeifer wrote most of
the form and menu libraries. Ongoing development work is done by
<a href="mailto:dickey@invisible-island.net">Thomas Dickey</a>.
Thomas Dickey also acts as the maintainer for the Free Software
Foundation, which holds the <a href=
"http://invisible-island.net/ncurses/ncurses-license.html">copyright
on ncurses</a>.</p>
<p>Contact the current maintainers at</p>
<blockquote>
<a href="mailto:bug-ncurses@gnu.org">bug-ncurses@gnu.org</a>
</blockquote>
<p>To join the ncurses mailing list, please write email to</p>
<blockquote>
<a href=
"mailto:bug-ncurses-request@gnu.org">bug-ncurses-request@gnu.org</a>
</blockquote>containing the line:
<blockquote>
<p><code>subscribe</code>
<em>&lt;name&gt;@&lt;host.domain&gt;</em></p>
</blockquote>
<p>This list is open to anyone interested in helping with the
development and testing of this package.</p>
<p>Beta versions of <em class="small-caps">ncurses</em> and
patches to the current release are made available at</p>
<blockquote>
<p><a href=
"ftp://invisible-island.net/ncurses/">ftp://invisible-island.net/ncurses/</a>&nbsp;.</p>
</blockquote>
<p>There is an archive of the mailing list here:</p>
<blockquote>
<p><a href=
"http://lists.gnu.org/archive/html/bug-ncurses">http://lists.gnu.org/archive/html/bug-ncurses</a>
(also <a href=
"https://lists.gnu.org/archive/html/bug-ncurses">https</a>)</p>
</blockquote>
<h2><a name="h2-this-stuff" id="h2-this-stuff">Related
resources</a></h2>
<p>The release notes make scattered references to these pages,
which may be interesting by themselves:</p>
<ul>
<li><a href=
"http://invisible-island.net/scripts/man2html.html">man2html</a></li>
<li><a href=
"http://invisible-island.nethttp://invisible-island.net/ncurses/ncurses-license.html">
<em class="small-caps">ncurses</em> licensing</a></li>
<li><a href=
"http://invisible-island.net/ncurses/ncurses-mapsyms.html">Symbol
versioning in <em class="small-caps">ncurses</em></a></li>
<li><a href=
"http://invisible-island.net/ncurses/ncurses-mingw.html">The
MinGW port of <em class="small-caps">ncurses</em></a></li>
<li><a href=
"http://invisible-island.net/ncurses/tack.html">tack &ndash;
terminfo action checker</a></li>
<li><a href=
"http://invisible-island.net/autoconf/portability-tar.html">tar
versus portability</a></li>
<li><a href=
"http://invisible-island.net/ncurses/tctest.html">tctest
&ndash; termcap library checker</a></li>
<li><a href=
"http://invisible-island.net/ncurses/ncurses.html#download_database">
Terminal Database</a></li>
</ul>
<h2><a name="h2-other-stuff" id="h2-other-stuff">Other
resources</a></h2>
<p>The distribution provides a newer version of the
terminfo-format terminal description file once maintained by
<a href="http://www.catb.org/~esr/terminfo/">Eric
Raymond</a>&nbsp;. 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.</p>
<p>You can find lots of information on terminal-related topics
not covered in the terminfo file at <a href=
"http://web.archive.org/web/*/http://www.cs.utk.edu/~shuford/terminal">
Richard Shuford's archive</a>&nbsp;.</p>
<div class="nav">
<ul>
<li><a href="#h2-overview">Overview</a></li>
<li>
<a href="#h2-release-notes">Release Notes</a>
<ul>
<li>
<a href="#h3-library">Library improvements</a>
<ul>
<li><a href="#h3-lib-setbuf">Output
buffering</a></li>
<li><a href="#h3-lib-versioning">Symbol
versioning</a></li>
<li><a href="#h3-lib-other">Miscellaneous</a></li>
</ul>
</li>
<li>
<a href="#h3-programs">Program improvements</a>
<ul>
<li><a href="#h4-utilities">Utilities</a></li>
<li><a href="#h4-examples">Examples</a></li>
</ul>
</li>
<li><a href="#h3-database">Terminal database</a></li>
<li><a href="#h3-documentation">Documentation</a></li>
<li><a href="#h3-bug-fixes">Interesting
bug-fixes</a></li>
<li>
<a href="#h3-config-config">Configuration changes</a>
<ul>
<li><a href="#h4-config-major">Major changes</a></li>
<li><a href="#h4-config-options">Configuration
options</a></li>
</ul>
</li>
<li>
<a href="#h3-portability">Portability</a>
<ul>
<li><a href="#h4-port-mingw">MinGW</a></li>
<li><a href="#h4-port-systems">Other ports</a></li>
</ul>
</li>
</ul>
</li>
<li><a href="#h2-features">Features of <em class=
"small-caps">ncurses</em></a></li>
<li><a href="#h2-who-uses">Applications using <em class=
"small-caps">ncurses</em></a></li>
<li><a href="#h2-development">Development activities</a></li>
<li><a href="#h2-this-stuff">Related resources</a></li>
<li><a href="#h2-other-stuff">Other resources</a></li>
</ul>
</div>
</body>
</html>