- Before ncurses 5.0, terminfo databases used a fixedrepertoire of
+ Before ncurses 5.0, terminfo databases used a fixedrepertoire of
terminal capabilities designed for the SVr2 terminal database in 1984,
- and extended in stages through SVr4 (1989), and standardized in the
- Single Unix Specification beginning in 1995.
+ and extended in stages through SVr4 (1989), and standardized in X/Open
+ Curses starting in 1995.
Most of the extensions in this fixed repertoire were additions to the
- tables of boolean, numeric and string capabilities. Rather than change
+ tables of Boolean, numeric and string capabilities. Rather than change
the meaning of an existing capability, a new name was added. The
terminfo database uses a binary format; binary compatibility was
ensured by using a header which gave the number of items in the tables
@@ -90,21 +92,21 @@
needed, while others were added (out of order) to comply with
X/Open Curses.
- While ncurses' repertoire of predefined capabilities is closest to
+ While ncurses' repertoire of predefined capabilities is closest to
Solaris, Solaris's terminfo database has a few differences from the
- list published by X/Open Curses. For example, ncurses can be
+ list published by X/Open Curses. For example, ncurses can be
configured with tables which match the terminal databases for AIX,
HP-UX or OSF/1, rather than the default Solaris-like configuration.
- o In SVr4 curses and ncurses, the terminal database is defined at
+ o In SVr4 curses and ncurses, the terminal database is defined at
compile-time using a text file which lists the different terminal
capabilities.
In principle, the text-file can be extended, but doing this
requires recompiling and reinstalling the library. The text-file
- used in ncurses for terminal capabilities includes details for
+ used in ncurses for terminal capabilities includes details for
various systems past the documented X/Open Curses features. For
- example, ncurses supports these capabilities in each configuration:
+ example, ncurses supports these capabilities in each configuration:
memory_lock
(meml) lock memory above cursor
@@ -133,13 +135,13 @@
Although termcap's extensibility was rarely used (it was never the
speaker who had actually used the feature), the criticism had a point.
- ncurses 5.0 provided a way to detect nonstandard capabilities,
+ ncurses 5.0 provided a way to detect nonstandard capabilities,
determine their type and optionally store and retrieve them in a way
which did not interfere with other applications. These are referred to
as user-definedcapabilities because no modifications to the toolset's
predefined capability names are needed.
- The ncurses utilities tic and infocmp have a command-line option "-x"
+ The ncurses utilities tic and infocmp have a command-line option "-x"
to control whether the nonstandard capabilities are stored or
retrieved. A library function use_extended_names is provided for the
same purpose.
@@ -148,7 +150,7 @@
user-defined capability if the capability name is not one of the
predefined names.
- Because ncurses provides a termcap library interface, these user-
+ Because ncurses provides a termcap library interface, these user-
defined capabilities may be visible to termcap applications:
o The termcap interface (like all implementations of termcap)
@@ -169,7 +171,7 @@
predefined function-key names, to which a series of keys can be
assigned, that is insufficient for more than a dozen keys
multiplied by more than a couple of modifier combinations. The
- ncurses database uses a convention based on xterm(1) to provide
+ ncurses database uses a convention based on xterm(1) to provide
extended special-key names.
Fitting that into termcap's limitation of 2-character names would
@@ -177,12 +179,12 @@
terminfo.
-
+ The ncurses library uses the user-definable capabilities. While the
+ terminfo database may have other extensions, ncurses makes explicit
checks for these:
- AX boolean, asserts that the terminal interprets SGR 39 and SGR 49
+ AX Boolean, asserts that the terminal interprets SGR 39 and SGR 49
by resetting the foreground and background color, respectively,
to the default.
@@ -194,24 +196,24 @@
The command "tputclear" does the same thing.
- NQ used to suppress a consistency check in tic for the ncurses
- capabilities in user6 through user9 (u6, u7, u8 and u9) which
- tell how to query the terminal's cursor position and its device
- attributes.
+ NQ Boolean, used to suppress a consistency check in tic for the
+ ncurses capabilities in user6 through user9 (u6, u7, u8 and u9)
+ which tell how to query the terminal's cursor position and its
+ device attributes.
RGB
- boolean, numberorstring, used to assert that the
+ Boolean, numberorstring, used to assert that the
set_a_foreground and set_a_background capabilities correspond to
directcolors, using an RGB (red/green/blue) convention. This
capability allows the color_content function to return
appropriate values without requiring the application to
initialize colors using init_color.
- The capability type determines the values which ncurses sees:
+ The capability type determines the values which ncurses sees:
- boolean
+ Boolean
implies that the number of bits for red, green and blue are
- the same. Using the maximum number of colors, ncurses adds
+ the same. Using the maximum number of colors, ncurses adds
two, divides that sum by three, and assigns the result to red,
green and blue in that order.
@@ -220,9 +222,9 @@
comparison to red.
number
- tells ncurses what result to add to red, green and blue. If
- ncurses runs out of bits, blue (and green) lose just as in the
- boolean case.
+ tells ncurses what result to add to red, green and blue. If
+ ncurses runs out of bits, blue (and green) lose just as in the
+ Boolean case.
string
explicitly list the number of bits used for red, green and
@@ -234,7 +236,7 @@
could define RGB#1 to represent the standard eight ANSI colors,
i.e., one bit per color.
- U8 number, asserts that ncurses must use Unicode values for line-
+ U8 number, asserts that ncurses must use Unicode values for line-
drawing characters, and that it should ignore the alternate
character set capabilities when the locale uses UTF-8 encoding.
For more information, see the discussion of NCURSES_NO_UTF8_ACS
@@ -242,16 +244,16 @@
Set this capability to a nonzero value to enable it.
- XM string, override ncurses's built-in string which enables/disables
+ XM string, override ncurses's built-in string which enables/disables
xterm(1) mouse mode.
- ncurses sends a character sequence to the terminal to initialize
+ ncurses sends a character sequence to the terminal to initialize
mouse mode, and when the user clicks the mouse buttons or (in
certain modes) moves the mouse, handles the characters sent back
by the terminal to tell it what was done with the mouse.
The mouse protocol is enabled when the mask passed in the
- mousemask function is nonzero. By default, ncurses handles the
+ mousemask function is nonzero. By default, ncurses handles the
responses for the X11 xterm mouse protocol. It also knows about
the SGR1006 xterm mouse protocol, but must to be told to look
for this specifically. It will not be able to guess which mode
@@ -260,7 +262,7 @@
The XM capability has a single parameter. If nonzero, the mouse
protocol should be enabled. If zero, the mouse protocol should
- be disabled. ncurses inspects this capability if it is present,
+ be disabled. ncurses inspects this capability if it is present,
to see whether the 1006 protocol is used. If so, it expects the
responses to use the SGR1006 xterm mouse protocol.
@@ -312,32 +314,39 @@
%?%p4%tM%em%;,
-
Several terminals provide the ability to send distinct strings for
combinations of modified special keys. There is no standard for what
those keys can send.
Since 1999, xterm(1) has supported shift, control, alt, and meta
modifiers which produce distinct special-key strings. In a terminal
- description, ncurses has no special knowledge of the modifiers used.
+ description, ncurses has no special knowledge of the modifiers used.
Applications can use the namingconvention established for xterm to
find these special keys in the terminal description.
- Starting with the curses convention that keynames begin with "k" and
- that shifted special keys are an uppercase name, ncurses' terminal
- database defines these names to which a suffix is added:
-
- NameDescription
- ---------------------------------------------------------------
- kDC special form of kdch1 (delete character)
- kDN special form of kcud1 (cursor down)
- kEND special form of kend (End)
- kHOM special form of khome (Home)
- kLFT special form of kcub1 (cursor-left or cursor-back)
- kNXT special form of knext (Next, or Page-Down)
- kPRV special form of kprev (Prev, or Page-Up)
- kRIT special form of kcuf1 (cursor-right, or cursor-forward)
- kUP special form of kcuu1 (cursor-up)
+ Starting with the curses convention that capability codes describing
+ the input generated by a terminal's key caps begin with "k", and that
+ shifted special keys use uppercase letters in their names, ncurses's
+ terminal database defines the following names and codes to which a
+ suffix is added.
+
+ CodeDescription
+ -------------------------------------------------------------------
+ kDC shifted kdch1 (delete character)
+ kDN shifted kcud1 (cursor down)
+ kEND shifted kend (end)
+ kHOM shifted khome (home)
+ kLFT shifted kcub1 (cursor back)
+ kNXT shifted knext (next)
+ kPRV shifted kprev (previous)
+ kRIT shifted kcuf1 (cursor forward)
+ kUP shifted kcuu1 (cursor up)
+
+ Keycap nomenclature on the Unix systems for which curses was developed
+ differs from today's ubiquitous descendants of the IBM PC/AT keyboard
+ layout. In the foregoing, interpret "backward" as "left", "forward" as
+ "right", "next" as "page down", and "prev(ious)" as "page up".
These are the suffixes used to denote the modifiers:
@@ -359,42 +368,42 @@
15 Meta + Ctrl + Alt
16 Meta + Ctrl + Alt + Shift
- None of these are predefined; terminal descriptions can refer to names
- which ncurses will allocate at runtime to key-codes. To use these keys
- in an ncurses program, an application could do this:
+ None of these are predefined; terminal descriptions can refer to names
+ which ncurses will allocate at runtime to key-codes. To use these keys
+ in an ncurses program, an application could do this:
- o using a list of extended key names, ask tigetstr(3x) for their
+ o using a list of extended key names, ask tigetstr(3x) for their
values, and
- o given the list of values, ask key_defined(3x) for the key-code
+ o given the list of values, ask key_defined(3x) for the key-code
which would be returned for those keys by wgetch(3x).
- The "-x" extension feature of tic and infocmp has been adopted in
- NetBSD curses. That implementation stores user-defined capabilities,
+ The "-x" extension feature of tic and infocmp has been adopted in
+ NetBSD curses. That implementation stores user-defined capabilities,
but makes no use of these capabilities itself.
+
- infocmp(1m), tic(1m).
+ infocmp(1m), tic(1m)
The terminal database section NCURSESUSER-DEFINABLECAPABILITIES
- summarizes commonly-used user-defined capabilities which are used in
- the terminal descriptions. Some of those features are mentioned in
+ summarizes commonly-used user-defined capabilities which are used in
+ the terminal descriptions. Some of those features are mentioned in
screen(1) or tmux(1).
- XTermControlSequences provides further information on the xterm(1)
- features which are used in these extended capabilities.
-
-
-
- Thomas E. Dickey
- beginning with ncurses 5.0 (1999)
+ XTermControlSequences provides further information on the xterm(1)
+ features that are used in these extended capabilities.
-ncurses 6.4 2023-09-09 user_caps(5)
+ncurses 6.5 2024-06-08 user_caps(5)