Announcing ncurses 5.6
The ncurses (new curses) library is a free software emulation of
curses in System V Release 4.0, and more.  It uses terminfo format,
supports pads and color
and multiple highlights and forms characters and function-key mapping,
and has all the other SYSV-curses enhancements over BSD curses.
In mid-June 1995, the maintainer of 4.4BSD curses declared that he
considered 4.4BSD curses obsolete, and encouraged the keepers of
Unix releases such as BSD/OS, FreeBSD and NetBSD to switch over to
ncurses.
The ncurses code was developed under GNU/Linux.
It has been in use for some time with OpenBSD as the system curses library,
and on FreeBSD and NetBSD as an external package.
It should port easily to any ANSI/POSIX-conforming UNIX.
It has even been ported to OS/2 Warp!
The distribution includes the library and support utilities, including a
terminfo compiler tic(1), a decompiler infocmp(1), clear(1), tput(1), tset(1),
and a termcap conversion tool captoinfo(1).  Full manual pages are provided for
the library and tools.
The ncurses distribution is available via anonymous FTP at
the GNU distribution site
ftp://ftp.gnu.org/gnu/ncurses/ .
It is also available at
ftp://invisible-island.net/ncurses/ .
Release Notes
This release is designed to be upward compatible from ncurses 5.0 through 5.5;
very few applications will require recompilation, depending on the platform.
These are the highlights from the change-log since ncurses 5.5 release.
Interface changes:
	- generate linkable stubs for some macros:
	
 getbegx, getbegy, getcurx, getcury, getmaxx, getmaxy, getparx,
	  getpary, getpary,
 and (for libncursesw)
 wgetbkgrnd
New features and improvements:
        - library
	
		- support hashed databases for the terminal descriptions.
		    This uses the Berkeley database, has been tested for
		    several versions on different platforms.
		
- add use_legacy_coding()function to support
		    lynx's font-switching feature.
- add extension nofilter(), to cancel a priorfilter()call.
- add/install a package config script, e.g.,
		    ncurses5-configorncursesw5-config, according to
		    configuration options.
- provide ifdef for NCURSES_NOMACROSwhich
		    suppresses most macro definitions from curses.h, i.e.,
		    where a macro is defined to override a function to improve
		    performance.
- make ifdef's consistent in curses.hfor the
		    extended colors so the header file can be used for the
		    normal curses library.  The header file installed for
		    extended colors is a variation of the wide-character
		    configuration.
- improve tgetstr()by making the return value
		    point into the user's buffer, if provided.
- add ifdef's allowing ncurses to be built with
		    tparm()using either varargs (the existing
		    status), or using a fixed-parameter list (to match X/Open).
- widen the test for xterm kmousa little toallowfor other
		    strings than "\E[M", e.g., forxterm-scofunctionality in xterm.
- modify wgetnstr()to returnKEY_RESIZEif a sigwinch occurs.
- move prototypes for wide-character trace functions from
		    curses.tail to curses.wide to avoid accidental reference to
		    those if _XOPEN_SOURCE_EXTENDEDis defined
		    without ensuring that <wchar.h> is included.
- change the way shared libraries (other than libtool) are
		    installed.  Rather than copying the build-tree's libraries,
		    link the shared objects into the install directory.  This
		    makes the --with-rpathoption work except with$(DESTDIR).
- several improvements for rendering in hpterm.  These are
		    only available if the library is configured using
		    --enable-xmc-glitch.
- Add NCURSES_NO_HARD_TABSandNCURSES_NO_MAGIC_COOKIEenvironment variables
		    to allow runtime suppression of the related hard-tabs and
		    xmc-glitch features.
 
- programs:
	
		- add new test programs:  chgat.c, demo_altkeys.c,
		    echochar.c, foldkeys.c, movewindow.c, redraw.c, (noting
		    that existing test programs also were modified to test
		    additional features).
		
- modify tack to test extended capability function-key
		    strings.
		
- modify toe to access termcap data, e.g., via cgetent()functions, or as a text file if those are not available.
- improve infocmp/tic -foption formatting.
- add toe -aoption, to show all databases. 
		    This uses new private interfaces in the ncurses library for
		    iterating through the list of databases.
- modify MKfallback.shto usetic -xwhen constructing fallback tables to
		    allow extended capabilities to be retrieved from a fallback entry.
 
- terminal database
	
		- add terminfo entries for xfce terminal (xfce) and multi gnome terminal (mgt)
		
- add nsterm-16color entry
		
- updated mlterm terminfo entry
		
- add kon, kon2 and jfbterm terminfo entry 
		
- remove invis capability from klone+sgr, mainly used by linux entry, since it does not really do this
		
- add ka2, kb1, kb3, kc2 to vt220-keypad as an extension
		
- add shifted up/down arrow codes to xterm-new as kind/kri strings
		
- add hpterm-color terminfo entry
		
- add 256color variants of terminfo entries for programs which are reported to implement this feature
		
- correct order of use-clauses in rxvt-basic entry which made codes for f1-f4 vt100-style rather than vt220-style.
	
 
Major bug fixes:
	- correct a typo in configure --with-booloption for the
	    case where--without-cxxis used.
- move assignment from environment variable ESCDELAYfrominitscr()down tonewterm()so the
	    environment variable affects timeouts for terminals opened with
	    newterm() as well.
- modify weraseto clear multicolumn characters that
	    extend into a derived window.
- modify wchgat()to mark updated cells as changed so a
	    refresh will repaint those cells.
- correct logic in wadd_wch()andwecho_wch(), which did not guard against passing the
	    multi-column attribute into a call onwaddch(), e.g.,
	    using data returned bywin_wch()
- fix redrawing of windows other than stdscrusingwredrawln()by touching the corresponding rows incurscr.
- reduce memory leaks in repeated calls to tgetent()by
	    remembering the lastTERMINAL*value allocated to hold
	    the corresponding data and freeing that if thetgetent()result buffer is the same as the previous
	    call.
- modify read_termtype()so theterm_namesdata is always allocated as part of thestr_table, a
	    better fix for a memory leak.
- fix wins_nwstr(),which did not handle single-column
	    non-8bit codes.
- modify wbkgrnd()to avoid clearing theA_CHARTEXTattribute bits since those record the state
	    of multicolumn characters.
- improve SIGWINCHhandling by postponing its effect
	    duringnewterm(), etc., when allocating screens.
- remove 970913 feature for copying subwindows as they are moved in
	    mvwin().
- add checks in waddchnstr()andwadd_wchnstr()to stop copying when a null character
	    is found.
- add some checks to ensure current position is within scrolling
	    region before scrolling on a new line.
	
- add a workaround to ACS mapping to allow applications such as
	    test/blue.c to use the "PC ROM" characters by masking them with
	    A_ALTCHARSET. This worked up til 5.5, but was lost in the revision
	    of legacy coding.
Portability:
        - configure script:
          
          - new options:
            
	    - --with-hashed-db
	    
- Use Berkeley hashed database for storing terminfo data rather than storing
		each compiled entry in a separate binary file within a directory
		tree.
	    
- --without-dlsym
	    
- Do not use dlsym()to load GPM dynamically.
- --with-valgrind
	    
- Simplify building for testing with valgrind.
	    
- --enable-wgetch-events
	    
- Compile with experimental wgetch-events code.
	    
- --enable-signed-char
	    
- Store booleans in "signed char" rather than "char".
            
 
- improved options:
	    
	    - --disable-largefile
	    
- make the option work both ways.
	    
- --with-gpm
	    
- The option now accepts a parameter,
		i.e., the name of the dynamic GPM library to load via
		dlopen()
- --disable-symlinks
	    
- The option now allows one to
		disable symlink()inticeven whenlink()does not work.
 
 
- other configure/build issues:   - remove special case for
	    Darwin in CF_XOPEN_SOURCEconfigure macro.
- add configure check to ensure that SIGWINCHis
		    defined on platforms such as OS X which exclude that when_XOPEN_SOURCE,etc., are defined
- use ld's -search_paths_firstoption on Darwin
		    to work around odd search rules on that platform.
- improve ifdef's for _POSIX_VDISABLEin tset to
                    work with Mac OS X.
- modify configure script to ensure that if the C compiler is
		    used rather than the loader in making shared libraries, the
		    $(CFLAGS)variable is also used.
- use ${CC}rather than${LD}in
		    shared library rules for IRIX64, Solaris to help ensure
		    that initialization sections are provided for extra linkage
		    requirements, e.g., of C++ applications.
- improve some shared-library configure scripting for Linux,
		    FreeBSD and NetBSD to make
		    --with-shlib-versionwork.
- split up dependency of names.candcodes.cinncurses/Makefileto
		    work with parallel make.
- modify MKlib_gen.shto change
                    preprocessor-expanded_Boolback tobool.
- modify progs/Makefile.into maketput initwork properly with cygwin,
		    i.e., do not pass a.exein the reference
		    string used in check_aliases.
 
- library:
	
		- ignore wide-acs line-drawing characters that
		    wcwidth()claims are not one-column.  This is
		    a workaround for Solaris' broken locale support.
- reduce name-pollution in term.hby removing#define's for HAVE_xxx symbols.
- fix #ifdefinc++/internal.hfor
		    QNX 6.1
 
- test programs:   - modify test/configurescript
	    to allow building test programs with PDCurses/X11.
- modified test programs to allow some to work with NetBSD
		    curses.  Several do not because NetBSD curses implements a
		    subset of X/Open curses, and also lacks much of SVr4
		    additions.  But it is enough for comparison.
		
- improved test/configureto build test/ncurses
		    on HPUX 11 using the vendor curses.
- change configure script to produce
		    test/Makefilefrom data file.
 
Features of Ncurses
The ncurses package is fully compatible with SVr4 (System V Release 4) curses:
- All 257 of the SVr4 calls have been implemented (and are documented).
- Full support for SVr4 curses features including keyboard mapping, color,
forms-drawing with ACS characters, and automatic recognition of keypad
and function keys.
- An emulation of the SVr4 panels library, supporting
a stack of windows with backing store, is included.
- An emulation of the SVr4 menus library, supporting
a uniform but flexible interface for menu programming, is included.
- An emulation of the SVr4 form library, supporting
data collection through on-screen forms, is included.
- Binary terminfo entries generated by the ncurses tic(1) implementation
are bit-for-bit-compatible with the entry format SVr4 curses uses.
- The utilities have options to allow you to filter terminfo
entries for use with less capable curses/terminfo
versions such as the HP/UX and AIX ports.
The ncurses package also has many useful extensions over SVr4:
- The API is 8-bit clean and base-level conformant with the X/OPEN curses
specification, XSI curses (that is, it implements all BASE level features,
and most EXTENDED features).
It includes many function calls not supported under SVr4 curses
(but portability of all
calls is documented so you can use the SVr4 subset only).
- Unlike SVr3 curses, ncurses can write to the rightmost-bottommost corner
of the screen if your terminal has an insert-character capability.
- Ada95 and C++ bindings.
- Support for mouse event reporting with X Window xterm
and FreeBSD and OS/2 console windows.
- Extended mouse support via Alessandro Rubini's gpm package.
- The function wresize()allows you to resize windows, preserving
their data.
- The function use_default_colors()allows you to
use the terminal's default colors for the default color pair,
achieving the effect of transparent colors.
- The functions keyok()anddefine_key()allow
you to better control the use of function keys,
e.g., disabling the ncurses KEY_MOUSE,
or by defining more than one control sequence to map to a given key code.
- Support for 16-color terminals, such as aixterm and modern xterm.
- Better cursor-movement optimization.  The package now features a
cursor-local-movement computation more efficient than either BSD's
or System V's.
- Super hardware scrolling support.  The screen-update code incorporates
a novel, simple, and cheap algorithm that enables it to make optimal
use of hardware scrolling, line-insertion, and line-deletion
for screen-line movements.  This algorithm is more powerful than
the 4.4BSD curses quickch() routine.
- Real support for terminals with the magic-cookie glitch.  The
screen-update code will refrain from drawing a highlight if the magic-
cookie unattributed spaces required just before the beginning and
after the end would step on a non-space character.  It will
automatically shift highlight boundaries when doing so would make it
possible to draw the highlight without changing the visual appearance
of the screen.
- It is possible to generate the library with a list of pre-loaded
fallback entries linked to it so that it can serve those terminal types even
when no terminfo tree or termcap file is accessible (this may be useful
for support of screen-oriented programs that must run in single-user mode).
- The tic(1)/captoinfo utility provided with ncurses has the
ability to translate many termcaps from the XENIX, IBM and
AT&T extension sets.
- A BSD-like tset(1) utility is provided.
- The ncurses library and utilities will automatically read terminfo
entries from $HOME/.terminfo if it exists, and compile to that directory
if it exists and the user has no write access to the system directory.
This feature makes it easier for users to have personal terminfo entries
without giving up access to the system terminfo directory.
- You may specify a path of directories to search for compiled
descriptions with the environment variable TERMINFO_DIRS (this
generalizes the feature provided by TERMINFO under stock System V.)
- In terminfo source files, use capabilities may refer not just to
other entries in the same source file (as in System V) but also to
compiled entries in either the system terminfo directory or the user's
$HOME/.terminfo directory.
- A script (capconvert) is provided to help BSD users
transition from termcap to terminfo.  It gathers the information in a
TERMCAP environment variable and/or a ~/.termcap local entries file
and converts it to an equivalent local terminfo tree under $HOME/.terminfo.
- Automatic fallback to the /etc/termcap file can be compiled in
when it is not possible to build a terminfo tree.  This feature is neither
fast nor cheap, you don't want to use it unless you have to,
but it's there.
- The table-of-entries utility toe makes it easy for users to
see exactly what terminal types are available on the system.
- The library meets the XSI requirement that every macro entry
point have a corresponding function which may be linked (and will be
prototype-checked) if the macro definition is disabled with
#undef.
- An HTML "Introduction to Programming with NCURSES" document provides
a narrative introduction to the curses programming interface.
State of the Package
Numerous bugs present in earlier versions have been fixed; the
library is far more reliable than it used to be.  Bounds checking in many
`dangerous' entry points has been improved.  The code is now type-safe
according to gcc -Wall.  The library has been checked for malloc leaks and
arena corruption by the Purify memory-allocation tester.
The ncurses code has been tested with a wide variety of applications
including (versions starting with those noted):
-  cdk
-  Curses Development Kit
 http://invisible-island.net/cdk/
 http://www.vexus.ca/products/CDK/
-  ded
-  directory-editor
 http://invisible-island.net/ded/
-  dialog
-  the underlying application used in Slackware's setup, and the basis
for similar applications on GNU/Linux.
 http://invisible-island.net/dialog/
-  lynx
-  the character-screen WWW browser
 http://lynx.isc.org/release/
-  Midnight Commander
-  file manager
 http://www.ibiblio.org/mc/
-  mutt
-  mail utility
 http://www.mutt.org/
-  ncftp
-  file-transfer utility
 http://www.ncftp.com/
-  nvi
-  New vi versions 1.50 are able to use ncurses versions 1.9.7 and later.
 http://www.bostic.com/vi/
 
-  pinfo
-  Lynx-like info browser.
http://dione.ids.pl/~pborys/software/pinfo/
-  tin
-  newsreader, supporting color, MIME
http://www.tin.org/
-  vh-1.6
-  Volks-Hypertext browser for the Jargon File
 http://www.debian.org/Packages/unstable/text/vh.html
as well as some that use ncurses for the terminfo support alone:
-  minicom
-  terminal emulator
 http://alioth.debian.org/projects/minicom/
-  vile
-  vi-like-emacs
 http://invisible-island.net/vile/
The ncurses distribution includes a selection of test programs (including
a few games).
Who's Who and What's What
Zeyd Ben-Halim
started it from a previous package pcurses, written by Pavel Curtis.
Eric S. Raymond
continued development.
Jürgen Pfeifer wrote most of the form and menu libraries.
Ongoing work is being done by
Thomas Dickey.
Thomas Dickey
acts as the maintainer for the Free Software Foundation,
which holds the copyright on ncurses.
Contact the current maintainers at
bug-ncurses@gnu.org.
To join the ncurses mailing list, please write email to
bug-ncurses-request@gnu.org containing the line:
             subscribe <name>@<host.domain>
This list is open to anyone interested in helping with the development and
testing of this package.
Beta versions of ncurses and patches to the current release are made available at
ftp://invisible-island.net/ncurses/ .
Future Plans
- Extended-level XPG4 conformance, with internationalization support.
- Ports to more systems, including DOS and Windows.
We need people to help with these projects.  If you are interested in working
on them, please join the ncurses list.Other Related Resources
The distribution provides a newer version of the terminfo-format
terminal description file once maintained by
Eric Raymond .
Unlike the older version, the termcap and terminfo data are provided
in the same file, and provides several user-definable extensions
beyond the X/Open specification.
You can find lots of information on terminal-related topics
not covered in the terminfo file at
Richard Shuford's
archive .