Provided by: ncurses-doc_6.4+20240113-1ubuntu2_all 
NAME
ncurses - character-cell terminal interface with optimized output
SYNOPSIS
#include <curses.h>
DESCRIPTION
The ncurses library routines give the user a terminal-independent method of updating
character screens with reasonable optimization. This implementation is “new curses” (‐
ncurses) and is the approved replacement for 4.4BSD classic curses, which has been
discontinued. This describes ncurses version 6.4 (patch 20240113).
The ncurses library emulates the curses library of System V Release 4 Unix (“SVr4”), and
XPG4 (X/Open Portability Guide) curses (also known as XSI curses). XSI stands for X/Open
System Interfaces Extension. The ncurses library is freely redistributable in source
form.
ncurses man pages employ several sections to clarify matters of usage and interoperability
with other curses implementations.
• “NOTES” describes matters and caveats of which any user of the ncurses API should be
aware, such as limitations on the size of an underlying integral type or the
availability of a preprocessor macro exclusive of a function definition (which
prevents its address from being taken). This section also describes implementation
details that will be significant to the programmer but which are not standardized.
• “EXTENSIONS” presents ncurses innovations beyond the X/Open Curses standard and/or the
SVr4 curses implementation. They are termed extensions to indicate that they cannot
be implemented solely by using the library API, but require access to the library's
internal state.
• “PORTABILITY” discusses matters (beyond the exercise of extensions) that should be
considered when writing to a curses standard, or to multiple implementations.
• “HISTORY” examines points of detail in ncurses and other curses implementations over
the decades of their development, particularly where precedent or inertia have
frustrated better design (and, in a few cases, where such inertia has been overcome).
A program using these routines must be linked with the -lncurses option, or (if it has
been generated) with the debugging library -lncurses_g. (Your system integrator may also
have installed these libraries under the names -lcurses and -lcurses_g.) The ncurses_g
library generates trace logs (in a file called “trace” in the current directory) that
describe curses actions. See section “ALTERNATE CONFIGURATIONS” below.
The ncurses package supports: overall screen, window and pad manipulation; output to
windows and pads; reading terminal input; control over terminal and curses input and
output options; environment query routines; color manipulation; use of soft label keys;
terminfo capabilities; and access to low-level terminal-manipulation routines.
Initialization
The library uses the locale which the calling program has initialized. That is normally
done with setlocale(3):
setlocale(LC_ALL, "");
If the locale is not initialized, the library assumes that characters are printable as in
ISO-8859-1, to work with certain legacy programs. You should initialize the locale and
not rely on specific details of the library when the locale has not been setup.
The function initscr or newterm must be called to initialize the library before any of the
other routines that deal with windows and screens are used. The routine endwin(3NCURSES)
must be called before exiting.
To get character-at-a-time input without echoing (most interactive, screen oriented
programs want this), the following sequence should be used:
initscr(); cbreak(); noecho();
Most programs would additionally use the sequence:
intrflush(stdscr, FALSE);
keypad(stdscr, TRUE);
Before a curses program is run, the tab stops of the terminal should be set and its
initialization strings, if defined, must be output. This can be done by executing the
tput init command after the shell environment variable TERM has been exported. (The BSD-
style tset(1) utility also performs this function.) See subsection “Tabs and
Initialization” of terminfo(5).
Overview
A curses library abstracts the terminal screen by representing all or part of it as a
WINDOW data structure. A window is a rectangular grid of character cells, addressed by
row and column coordinates (y, x), with the upper left corner as (0, 0). A window called
stdscr, the same size as the terminal screen, is always available. Create others with
newwin(3NCURSES).
A curses library does not manage overlapping windows. (See panel(3NCURSES) if you desire
this.) You can either use stdscr to manage one screen-filling window, or tile the screen
into non-overlapping windows and not use stdscr at all. Mixing the two approaches will
result in unpredictable, and undesired, effects.
Functions permit manipulation of a window and the cursor identifying the cell within it at
which the next output operation will occur. Among those, the most basic are
move(3NCURSES) and addch(3NCURSES): these place the cursor and write a character to
stdscr, respectively. As a rule, window-addressing functions feature names prefixed (or
infixed, see below) with “w”; these allow the user to specify a pointer to a WINDOW.
Counterparts not thus prefixed (or infixed) affect stdscr. Because moving the cursor
prior to another operation is so common, curses generally also provides functions with a
“mv” prefix as a convenience. Thus, the library defines all of addch, waddch, mvaddch,
and mvwaddch. When both prefixes are present, the order of arguments is a WINDOW pointer
first, then a y and x coordinate pair.
Updating the terminal screen with every curses call can cause unpleasant flicker or
inefficient use of the communications channel to the device. Therefore, after using
curses functions to accumulate a set of desired updates that make sense to present
together, call refresh(3NCURSES) to tell the library to make the user's screen look like
stdscr. ncurses optimizes its output by computing a minimal number of operations to
mutate the screen from its state at the previous refresh to the new one. Effective
optimization demands accurate information about the terminal device: the management of
such information is the province of the terminfo(3NCURSES) API, a feature of every
standard curses implementation.
Special windows called pads may also be manipulated. These are windows that are not
constrained to the size of the terminal screen and whose contents need not be completely
displayed. See pad(3NCURSES).
In addition to drawing characters on the screen, rendering attributes and colors may be
supported, causing the characters to show up in such modes as underlined, in reverse
video, or in color on terminals that support such display enhancements. See
attr(3NCURSES).
curses predefines constants for a small set of line-drawing and other graphics
corresponding to the DEC Alternate Character Set (ACS), a feature of VT100 and other
terminals. See waddch(3NCURSES) and wadd_wch(3NCURSES).
curses is implemented using the operating system's terminal driver; keystroke events are
received not as scan codes but as byte sequences. Graphical keycaps (alphanumeric and
punctuation keys, and the space) appear as-is. Everything else, including the tab,
enter/return, keypad, arrow, and function keys, appears as a control character or a
multibyte escape sequence. curses translates these into unique key codes. See
getch(3NCURSES).
Effects of GUIs and Environment Variables
The selection of an appropriate value of TERM in the process environment is essential to
correct curses and terminfo library operation. A well-configured system selects a correct
TERM value automatically; tset(1) may assist with troubleshooting exotic situations.
If the environment variables LINES and COLUMNS are set, or if the curses program is
executing in a graphical windowing environment, the information obtained thence overrides
that obtained by terminfo. An ncurses extension supports resizable terminals; see
wresize(3NCURSES).
If the environment variable TERMINFO is defined, a curses program checks first for a
terminal type description in the location it identifies. TERMINFO is useful for
developing experimental type descriptions or when write permission to /etc/terminfo is not
available.
See section “ENVIRONMENT” below.
Naming Conventions
Many curses functions have two or more versions. Those prefixed with “w” require a window
argument. Four functions prefixed with “p” require a pad argument. Those without a
prefix generally operate on stdscr.
In function synopses, ncurses man pages apply the following names to parameters.
bf bool (TRUE or FALSE)
win pointer to WINDOW
pad pointer to WINDOW that is a pad
Wide and Non-wide Character Configurations
This manual page describes functions that appear in any configuration of the library.
There are two common configurations; see section “ALTERNATE CONFIGURATIONS” below.
ncurses is the library in its “non-wide” configuration, handling only eight-bit
characters. It stores a character combined with attributes in a chtype datum,
which is often an alias of int.
Attributes alone (with no corresponding character) can be stored in variables of
chtype or attr_t type. In either case, they are represented as an integral bit
mask.
Each cell of a WINDOW is stored as a chtype.
ncursesw is the library in its “wide” configuration, which handles character encodings
requiring a larger data type than char (a byte-sized type) can represent. It
adds about one third more calls using additional data types that can store such
multibyte characters.
cchar_t corresponds to the non-wide configuration's chtype. It always a
structure type, because it stores more data than fits into an integral
type. A character code may not be representable as a char, and
moreover more than one character may occupy a cell (as with accent
marks and other diacritics). Each character is of type wchar_t; a
complex character contains one spacing character and zero or more non-
spacing characters (see below). Attributes and color data are stored
in separate fields of the structure, not combined as in chtype.
Each cell of a WINDOW is stored as a cchar_t.
The setcchar(3NCURSES) and getcchar(3NCURSES) functions store and retrieve the
data from a cchar_t structure. The wide library API of ncurses depends on two
data types standardized by ISO C95.
wchar_t stores a wide character. Like chtype, it may be an alias of int.
Depending on the character encoding, a wide character may be spacing,
meaning that it occupies a character cell by itself and typically
accompanies cursor advancement, or non-spacing, meaning that it
occupies the same cell as a spacing character, is often regarded as a
“modifier” of the base glyph with which it combines, and typically does
not advance the cursor.
wint_t can store a wchar_t or the constant WEOF, analogously to the int-sized
character manipulation functions of ISO C and its constant EOF.
The wide library provides additional functions that complement those in the non-
wide library where the size of the underlying character type is significant. A
somewhat regular naming convention relates many of the wide variants to their
non-wide counterparts; where a non-wide function name contains “ch” or “str”,
prefix it with “_w” to obtain the wide counterpart. For example, waddch becomes
wadd_wch.
This convention is inapplicable to some non-wide function names, so other
transformations are used for the wide configuration: in the window background
management functions, “bkgd” becomes “bkgrnd”; the window border-drawing and
-clearing functions are suffixed with “_set”.
Function Name Index
The following table lists the curses functions provided in the non-wide and wide APIs and
the corresponding man pages that describe them. Those flagged with “*” are
ncurses-specific, neither described by X/Open Curses nor present in SVr4.
curses Function Name Man Page
───────────────────────────────────────────────────
COLOR_PAIR color(3NCURSES)
PAIR_NUMBER color(3NCURSES)
add_wch add_wch(3NCURSES)
add_wchnstr add_wchstr(3NCURSES)
add_wchstr add_wchstr(3NCURSES)
addch addch(3NCURSES)
addchnstr addchstr(3NCURSES)
addchstr addchstr(3NCURSES)
addnstr addstr(3NCURSES)
addnwstr addwstr(3NCURSES)
addstr addstr(3NCURSES)
addwstr addwstr(3NCURSES)
alloc_pair new_pair(3NCURSES)*
assume_default_colors default_colors(3NCURSES)*
attr_get attr(3NCURSES)
attr_off attr(3NCURSES)
attr_on attr(3NCURSES)
attr_set attr(3NCURSES)
attroff attr(3NCURSES)
attron attr(3NCURSES)
attrset attr(3NCURSES)
baudrate termattrs(3NCURSES)
beep beep(3NCURSES)
bkgd bkgd(3NCURSES)
bkgdset bkgd(3NCURSES)
bkgrnd bkgrnd(3NCURSES)
bkgrndset bkgrnd(3NCURSES)
border border(3NCURSES)
border_set border_set(3NCURSES)
box border(3NCURSES)
box_set border_set(3NCURSES)
can_change_color color(3NCURSES)
cbreak inopts(3NCURSES)
chgat attr(3NCURSES)
clear clear(3NCURSES)
clearok outopts(3NCURSES)
clrtobot clear(3NCURSES)
clrtoeol clear(3NCURSES)
color_content color(3NCURSES)
color_set attr(3NCURSES)
copywin overlay(3NCURSES)
curs_set kernel(3NCURSES)
curses_trace trace(3NCURSES)*
curses_version extensions(3NCURSES)*
def_prog_mode kernel(3NCURSES)
def_shell_mode kernel(3NCURSES)
define_key define_key(3NCURSES)*
del_curterm terminfo(3NCURSES)
delay_output util(3NCURSES)
delch delch(3NCURSES)
deleteln deleteln(3NCURSES)
delscreen initscr(3NCURSES)
delwin window(3NCURSES)
derwin window(3NCURSES)
doupdate refresh(3NCURSES)
dupwin window(3NCURSES)
echo inopts(3NCURSES)
echo_wchar add_wch(3NCURSES)
echochar addch(3NCURSES)
endwin initscr(3NCURSES)
erase clear(3NCURSES)
erasechar termattrs(3NCURSES)
erasewchar termattrs(3NCURSES)
exit_curses memleaks(3NCURSES)*
exit_terminfo memleaks(3NCURSES)*
extended_color_content color(3NCURSES)*
extended_pair_content color(3NCURSES)*
extended_slk_color slk(3NCURSES)*
filter util(3NCURSES)
find_pair new_pair(3NCURSES)*
flash beep(3NCURSES)
flushinp util(3NCURSES)
free_pair new_pair(3NCURSES)*
get_wch get_wch(3NCURSES)
get_wstr get_wstr(3NCURSES)
getattrs attr(3NCURSES)
getbegx legacy(3NCURSES)*
getbegy legacy(3NCURSES)*
getbegyx getyx(3NCURSES)
getbkgd bkgd(3NCURSES)
getbkgrnd bkgrnd(3NCURSES)
getcchar getcchar(3NCURSES)
getch getch(3NCURSES)
getcurx legacy(3NCURSES)*
getcury legacy(3NCURSES)*
getmaxx legacy(3NCURSES)*
getmaxy legacy(3NCURSES)*
getmaxyx getyx(3NCURSES)
getmouse mouse(3NCURSES)*
getn_wstr get_wstr(3NCURSES)
getnstr getstr(3NCURSES)
getparx legacy(3NCURSES)*
getpary legacy(3NCURSES)*
getparyx getyx(3NCURSES)
getstr getstr(3NCURSES)
getsyx kernel(3NCURSES)
getwin util(3NCURSES)
getyx getyx(3NCURSES)
halfdelay inopts(3NCURSES)
has_colors color(3NCURSES)
has_ic termattrs(3NCURSES)
has_il termattrs(3NCURSES)
has_key getch(3NCURSES)*
has_mouse mouse(3NCURSES)*
hline border(3NCURSES)
hline_set border_set(3NCURSES)
idcok outopts(3NCURSES)
idlok outopts(3NCURSES)
immedok outopts(3NCURSES)
in_wch in_wch(3NCURSES)
in_wchnstr in_wchstr(3NCURSES)
in_wchstr in_wchstr(3NCURSES)
inch inch(3NCURSES)
inchnstr inchstr(3NCURSES)
inchstr inchstr(3NCURSES)
init_color color(3NCURSES)
init_extended_color color(3NCURSES)*
init_extended_pair color(3NCURSES)*
init_pair color(3NCURSES)
initscr initscr(3NCURSES)
innstr instr(3NCURSES)
innwstr inwstr(3NCURSES)
ins_nwstr ins_wstr(3NCURSES)
ins_wch ins_wch(3NCURSES)
ins_wstr ins_wstr(3NCURSES)
insch insch(3NCURSES)
insdelln deleteln(3NCURSES)
insertln deleteln(3NCURSES)
insnstr insstr(3NCURSES)
insstr insstr(3NCURSES)
instr instr(3NCURSES)
intrflush inopts(3NCURSES)
inwstr inwstr(3NCURSES)
is_cbreak inopts(3NCURSES)*
is_cleared opaque(3NCURSES)*
is_echo inopts(3NCURSES)*
is_idcok opaque(3NCURSES)*
is_idlok opaque(3NCURSES)*
is_immedok opaque(3NCURSES)*
is_keypad opaque(3NCURSES)*
is_leaveok opaque(3NCURSES)*
is_linetouched touch(3NCURSES)
is_nl inopts(3NCURSES)*
is_nodelay opaque(3NCURSES)*
is_notimeout opaque(3NCURSES)*
is_pad opaque(3NCURSES)*
is_raw inopts(3NCURSES)*
is_scrollok opaque(3NCURSES)*
is_subwin opaque(3NCURSES)*
is_syncok opaque(3NCURSES)*
is_term_resized resizeterm(3NCURSES)*
is_wintouched touch(3NCURSES)
isendwin initscr(3NCURSES)
key_defined key_defined(3NCURSES)*
key_name util(3NCURSES)
keybound keybound(3NCURSES)*
keyname util(3NCURSES)
keyok keyok(3NCURSES)*
keypad inopts(3NCURSES)
killchar termattrs(3NCURSES)
killwchar termattrs(3NCURSES)
leaveok outopts(3NCURSES)
longname termattrs(3NCURSES)
mcprint print(3NCURSES)*
meta inopts(3NCURSES)
mouse_trafo mouse(3NCURSES)*
mouseinterval mouse(3NCURSES)*
mousemask mouse(3NCURSES)*
move move(3NCURSES)
mvadd_wch add_wch(3NCURSES)
mvadd_wchnstr add_wchstr(3NCURSES)
mvadd_wchstr add_wchstr(3NCURSES)
mvaddch addch(3NCURSES)
mvaddchnstr addchstr(3NCURSES)
mvaddchstr addchstr(3NCURSES)
mvaddnstr addstr(3NCURSES)
mvaddnwstr addwstr(3NCURSES)
mvaddstr addstr(3NCURSES)
mvaddwstr addwstr(3NCURSES)
mvchgat attr(3NCURSES)
mvcur terminfo(3NCURSES)
mvdelch delch(3NCURSES)
mvderwin window(3NCURSES)
mvget_wch get_wch(3NCURSES)
mvget_wstr get_wstr(3NCURSES)
mvgetch getch(3NCURSES)
mvgetn_wstr get_wstr(3NCURSES)
mvgetnstr getstr(3NCURSES)
mvgetstr getstr(3NCURSES)
mvhline border(3NCURSES)
mvhline_set border_set(3NCURSES)
mvin_wch in_wch(3NCURSES)
mvin_wchnstr in_wchstr(3NCURSES)
mvin_wchstr in_wchstr(3NCURSES)
mvinch inch(3NCURSES)
mvinchnstr inchstr(3NCURSES)
mvinchstr inchstr(3NCURSES)
mvinnstr instr(3NCURSES)
mvinnwstr inwstr(3NCURSES)
mvins_nwstr ins_wstr(3NCURSES)
mvins_wch ins_wch(3NCURSES)
mvins_wstr ins_wstr(3NCURSES)
mvinsch insch(3NCURSES)
mvinsnstr insstr(3NCURSES)
mvinsstr insstr(3NCURSES)
mvinstr instr(3NCURSES)
mvinwstr inwstr(3NCURSES)
mvprintw printw(3NCURSES)
mvscanw scanw(3NCURSES)
mvvline border(3NCURSES)
mvvline_set border_set(3NCURSES)
mvwadd_wch add_wch(3NCURSES)
mvwadd_wchnstr add_wchstr(3NCURSES)
mvwadd_wchstr add_wchstr(3NCURSES)
mvwaddch addch(3NCURSES)
mvwaddchnstr addchstr(3NCURSES)
mvwaddchstr addchstr(3NCURSES)
mvwaddnstr addstr(3NCURSES)
mvwaddnwstr addwstr(3NCURSES)
mvwaddstr addstr(3NCURSES)
mvwaddwstr addwstr(3NCURSES)
mvwchgat attr(3NCURSES)
mvwdelch delch(3NCURSES)
mvwget_wch get_wch(3NCURSES)
mvwget_wstr get_wstr(3NCURSES)
mvwgetch getch(3NCURSES)
mvwgetn_wstr get_wstr(3NCURSES)
mvwgetnstr getstr(3NCURSES)
mvwgetstr getstr(3NCURSES)
mvwhline border(3NCURSES)
mvwhline_set border_set(3NCURSES)
mvwin window(3NCURSES)
mvwin_wch in_wch(3NCURSES)
mvwin_wchnstr in_wchstr(3NCURSES)
mvwin_wchstr in_wchstr(3NCURSES)
mvwinch inch(3NCURSES)
mvwinchnstr inchstr(3NCURSES)
mvwinchstr inchstr(3NCURSES)
mvwinnstr instr(3NCURSES)
mvwinnwstr inwstr(3NCURSES)
mvwins_nwstr ins_wstr(3NCURSES)
mvwins_wch ins_wch(3NCURSES)
mvwins_wstr ins_wstr(3NCURSES)
mvwinsch insch(3NCURSES)
mvwinsnstr insstr(3NCURSES)
mvwinsstr insstr(3NCURSES)
mvwinstr instr(3NCURSES)
mvwinwstr inwstr(3NCURSES)
mvwprintw printw(3NCURSES)
mvwscanw scanw(3NCURSES)
mvwvline border(3NCURSES)
mvwvline_set border_set(3NCURSES)
napms kernel(3NCURSES)
newpad pad(3NCURSES)
newterm initscr(3NCURSES)
newwin window(3NCURSES)
nl inopts(3NCURSES)
nocbreak inopts(3NCURSES)
nodelay inopts(3NCURSES)
noecho inopts(3NCURSES)
nofilter util(3NCURSES)*
nonl inopts(3NCURSES)
noqiflush inopts(3NCURSES)
noraw inopts(3NCURSES)
notimeout inopts(3NCURSES)
overlay overlay(3NCURSES)
overwrite overlay(3NCURSES)
pair_content color(3NCURSES)
pecho_wchar pad(3NCURSES)
pechochar pad(3NCURSES)
pnoutrefresh pad(3NCURSES)
prefresh pad(3NCURSES)
printw printw(3NCURSES)
putp terminfo(3NCURSES)
putwin util(3NCURSES)
qiflush inopts(3NCURSES)
raw inopts(3NCURSES)
redrawwin refresh(3NCURSES)
refresh refresh(3NCURSES)
reset_color_pairs color(3NCURSES)*
reset_prog_mode kernel(3NCURSES)
reset_shell_mode kernel(3NCURSES)
resetty kernel(3NCURSES)
resize_term resizeterm(3NCURSES)*
resizeterm resizeterm(3NCURSES)*
restartterm terminfo(3NCURSES)
ripoffline kernel(3NCURSES)
savetty kernel(3NCURSES)
scanw scanw(3NCURSES)
scr_dump scr_dump(3NCURSES)
scr_init scr_dump(3NCURSES)
scr_restore scr_dump(3NCURSES)
scr_set scr_dump(3NCURSES)
scrl scroll(3NCURSES)
scroll scroll(3NCURSES)
scrollok outopts(3NCURSES)
set_curterm terminfo(3NCURSES)
set_term initscr(3NCURSES)
setcchar getcchar(3NCURSES)
setscrreg outopts(3NCURSES)
setsyx kernel(3NCURSES)
setupterm terminfo(3NCURSES)
slk_attr slk(3NCURSES)*
slk_attr_off slk(3NCURSES)
slk_attr_on slk(3NCURSES)
slk_attr_set slk(3NCURSES)
slk_attroff slk(3NCURSES)
slk_attron slk(3NCURSES)
slk_attrset slk(3NCURSES)
slk_clear slk(3NCURSES)
slk_color slk(3NCURSES)
slk_init slk(3NCURSES)
slk_label slk(3NCURSES)
slk_noutrefresh slk(3NCURSES)
slk_refresh slk(3NCURSES)
slk_restore slk(3NCURSES)
slk_set slk(3NCURSES)
slk_touch slk(3NCURSES)
slk_wset slk(3NCURSES)
standend attr(3NCURSES)
standout attr(3NCURSES)
start_color color(3NCURSES)
subpad pad(3NCURSES)
subwin window(3NCURSES)
syncok window(3NCURSES)
term_attrs termattrs(3NCURSES)
termattrs termattrs(3NCURSES)
termname termattrs(3NCURSES)
tgetent termcap(3NCURSES)
tgetflag termcap(3NCURSES)
tgetnum termcap(3NCURSES)
tgetstr termcap(3NCURSES)
tgoto termcap(3NCURSES)
tigetflag terminfo(3NCURSES)
tigetnum terminfo(3NCURSES)
tigetstr terminfo(3NCURSES)
timeout inopts(3NCURSES)
tiparm terminfo(3NCURSES)
tiparm_s terminfo(3NCURSES)*
tiscan_s terminfo(3NCURSES)*
touchline touch(3NCURSES)
touchwin touch(3NCURSES)
tparm terminfo(3NCURSES)
tputs termcap(3NCURSES)
tputs terminfo(3NCURSES)
trace trace(3NCURSES)*
typeahead inopts(3NCURSES)
unctrl util(3NCURSES)
unget_wch get_wch(3NCURSES)
ungetch getch(3NCURSES)
ungetmouse mouse(3NCURSES)*
untouchwin touch(3NCURSES)
use_default_colors default_colors(3NCURSES)*
use_env util(3NCURSES)
use_extended_names extensions(3NCURSES)*
use_legacy_coding legacy_coding(3NCURSES)*
use_tioctl util(3NCURSES)*
vid_attr terminfo(3NCURSES)
vid_puts terminfo(3NCURSES)
vidattr terminfo(3NCURSES)
vidputs terminfo(3NCURSES)
vline border(3NCURSES)
vline_set border_set(3NCURSES)
vw_printw printw(3NCURSES)
vw_scanw scanw(3NCURSES)
vwprintw printw(3NCURSES)
vwscanw scanw(3NCURSES)
wadd_wch add_wch(3NCURSES)
wadd_wchnstr add_wchstr(3NCURSES)
wadd_wchstr add_wchstr(3NCURSES)
waddch addch(3NCURSES)
waddchnstr addchstr(3NCURSES)
waddchstr addchstr(3NCURSES)
waddnstr addstr(3NCURSES)
waddnwstr addwstr(3NCURSES)
waddstr addstr(3NCURSES)
waddwstr addwstr(3NCURSES)
wattr_get attr(3NCURSES)
wattr_off attr(3NCURSES)
wattr_on attr(3NCURSES)
wattr_set attr(3NCURSES)
wattroff attr(3NCURSES)
wattron attr(3NCURSES)
wattrset attr(3NCURSES)
wbkgd bkgd(3NCURSES)
wbkgdset bkgd(3NCURSES)
wbkgrnd bkgrnd(3NCURSES)
wbkgrndset bkgrnd(3NCURSES)
wborder border(3NCURSES)
wborder_set border_set(3NCURSES)
wchgat attr(3NCURSES)
wclear clear(3NCURSES)
wclrtobot clear(3NCURSES)
wclrtoeol clear(3NCURSES)
wcolor_set attr(3NCURSES)
wcursyncup window(3NCURSES)
wdelch delch(3NCURSES)
wdeleteln deleteln(3NCURSES)
wecho_wchar add_wch(3NCURSES)
wechochar addch(3NCURSES)
wenclose mouse(3NCURSES)*
werase clear(3NCURSES)
wget_wch get_wch(3NCURSES)
wget_wstr get_wstr(3NCURSES)
wgetbkgrnd bkgrnd(3NCURSES)
wgetch getch(3NCURSES)
wgetdelay opaque(3NCURSES)*
wgetn_wstr get_wstr(3NCURSES)
wgetnstr getstr(3NCURSES)
wgetparent opaque(3NCURSES)*
wgetscrreg opaque(3NCURSES)*
wgetstr getstr(3NCURSES)
whline border(3NCURSES)
whline_set border_set(3NCURSES)
win_wch in_wch(3NCURSES)
win_wchnstr in_wchstr(3NCURSES)
win_wchstr in_wchstr(3NCURSES)
winch inch(3NCURSES)
winchnstr inchstr(3NCURSES)
winchstr inchstr(3NCURSES)
winnstr instr(3NCURSES)
winnwstr inwstr(3NCURSES)
wins_nwstr ins_wstr(3NCURSES)
wins_wch ins_wch(3NCURSES)
wins_wstr ins_wstr(3NCURSES)
winsch insch(3NCURSES)
winsdelln deleteln(3NCURSES)
winsertln deleteln(3NCURSES)
winsnstr insstr(3NCURSES)
winsstr insstr(3NCURSES)
winstr instr(3NCURSES)
winwstr inwstr(3NCURSES)
wmouse_trafo mouse(3NCURSES)*
wmove move(3NCURSES)
wnoutrefresh refresh(3NCURSES)
wprintw printw(3NCURSES)
wredrawln refresh(3NCURSES)
wrefresh refresh(3NCURSES)
wresize wresize(3NCURSES)*
wscanw scanw(3NCURSES)
wscrl scroll(3NCURSES)
wsetscrreg outopts(3NCURSES)
wstandend attr(3NCURSES)
wstandout attr(3NCURSES)
wsyncdown window(3NCURSES)
wsyncup window(3NCURSES)
wtimeout inopts(3NCURSES)
wtouchln touch(3NCURSES)
wunctrl util(3NCURSES)
wvline border(3NCURSES)
wvline_set border_set(3NCURSES)
Depending on the configuration, additional sets of functions may be available:
memleaks(3NCURSES) - curses memory-leak checking
sp_funcs(3NCURSES) - curses screen-pointer extension
threads(3NCURSES) - curses thread support
trace(3NCURSES) - curses debugging routines
RETURN VALUE
Unless otherwise noted, functions that return an integer return OK on success and ERR on
failure. Functions that return pointers return NULL on failure. Typically, ncurses
treats a null pointer passed as a function parameter as a failure.
Functions with a “mv” prefix first perform cursor movement using wmove and fail if the
position is outside the window, or (for “mvw” functions) if the WINDOW pointer is null.
ENVIRONMENT
The following environment symbols are useful for customizing the runtime behavior of the
ncurses library. The most important ones have been already discussed in detail.
CC (command character)
When set, change the command_character (cmdch) capability value of loaded terminfo entries
to the value of this variable. Very few terminfo entries provide this feature.
Because this name is also used in development environments to represent the C compiler's
name, ncurses ignores it if it does not happen to be a single character.
BAUDRATE
The debugging library checks this environment variable when the application has redirected
output to a file. The variable's numeric value is used for the baudrate. If no value is
found, ncurses uses 9600. This allows testers to construct repeatable test-cases that
take into account costs that depend on baudrate.
COLUMNS
Specify the width of the screen in characters. Applications running in a windowing
environment usually are able to obtain the width of the window in which they are
executing. If neither the COLUMNS value nor the terminal's screen size is available,
ncurses uses the size which may be specified in the terminfo database (i.e., the cols
capability).
It is important that your application use a correct size for the screen. This is not
always possible because your application may be running on a host which does not honor
NAWS (Negotiations About Window Size), or because you are temporarily running as another
user. However, setting COLUMNS and/or LINES overrides the library's use of the screen
size obtained from the operating system.
Either COLUMNS or LINES symbols may be specified independently. This is mainly useful to
circumvent legacy misfeatures of terminal descriptions, e.g., xterm which commonly
specifies a 65 line screen. For best results, lines and cols should not be specified in a
terminal description for terminals which are run as emulations.
Use the use_env function to disable all use of external environment (but not including
system calls) to determine the screen size. Use the use_tioctl function to update COLUMNS
or LINES to match the screen size obtained from system calls or the terminal database.
ESCDELAY
Specifies the total time, in milliseconds, for which ncurses will await a character
sequence, e.g., a function key. The default value, 1000 milliseconds, is enough for most
uses. However, it is made a variable to accommodate unusual applications.
The most common instance where you may wish to change this value is to work with slow
hosts, e.g., running on a network. If the host cannot read characters rapidly enough, it
will have the same effect as if the terminal did not send characters rapidly enough. The
library will still see a timeout.
Note that xterm mouse events are built up from character sequences received from the
xterm. If your application makes heavy use of multiple-clicking, you may wish to lengthen
this default value because the timeout applies to the composed multi-click event as well
as the individual clicks.
In addition to the environment variable, this implementation provides a global variable
with the same name. Portable applications should not rely upon the presence of ESCDELAY
in either form, but setting the environment variable rather than the global variable does
not create problems when compiling an application.
HOME
Tells ncurses where your home directory is. That is where it may read and write auxiliary
terminal descriptions:
$HOME/.termcap
$HOME/.terminfo
LINES
Like COLUMNS, specify the height of the screen in characters. See COLUMNS for a detailed
description.
MOUSE_BUTTONS_123
This applies only to the OS/2 EMX port. It specifies the order of buttons on the mouse.
OS/2 numbers a 3-button mouse inconsistently from other platforms:
1 = left
2 = right
3 = middle.
This variable lets you customize the mouse. The variable must be three numeric digits 1-3
in any order, e.g., 123 or 321. If it is not specified, ncurses uses 132.
NCURSES_ASSUMED_COLORS
Override the compiled-in assumption that the terminal's default colors are white-on-black
(see default_colors(3NCURSES)). You may set the foreground and background color values
with this environment variable by proving a 2-element list: foreground,background. For
example, to tell ncurses to not assume anything about the colors, set this to "-1,-1". To
make it green-on-black, set it to "2,0". Any positive value from zero to the terminfo
max_colors value is allowed.
NCURSES_CONSOLE2
This applies only to the MinGW port of ncurses.
The Console2 program's handling of the Microsoft Console API call
CreateConsoleScreenBuffer is defective. Applications which use this will hang. However,
it is possible to simulate the action of this call by mapping coordinates, explicitly
saving and restoring the original screen contents. Setting the environment variable NCGDB
has the same effect.
NCURSES_GPM_TERMS
This applies only to ncurses configured to use the GPM interface.
If present, the environment variable is a list of one or more terminal names against which
the TERM environment variable is matched. Setting it to an empty value disables the GPM
interface; using the built-in support for xterm, etc.
If the environment variable is absent, ncurses will attempt to open GPM if TERM contains
“linux”.
NCURSES_NO_HARD_TABS
ncurses may use tabs as part of cursor movement optimization. In some cases, your
terminal driver may not handle these properly. Set this environment variable to any value
to disable the feature. You can also adjust your stty(1) settings to avoid the problem.
NCURSES_NO_MAGIC_COOKIE
Some terminals use a magic-cookie feature which requires special handling to make
highlighting and other video attributes display properly. You can suppress the
highlighting entirely for these terminals by setting this environment variable to any
value.
NCURSES_NO_PADDING
Most of the terminal descriptions in the terminfo database are written for real “hardware”
terminals. Many people use terminal emulators which run in a windowing environment and
use curses-based applications. Terminal emulators can duplicate all of the important
aspects of a hardware terminal, but they do not have the same limitations. The chief
limitation of a hardware terminal from the standpoint of your application is the
management of dataflow, i.e., timing. Unless a hardware terminal is interfaced into a
terminal concentrator (which does flow control), it (or your application) must manage
dataflow, preventing overruns. The cheapest solution (no hardware cost) is for your
program to do this by pausing after operations that the terminal does slowly, such as
clearing the display.
As a result, many terminal descriptions (including the vt100) have delay times embedded.
You may wish to use these descriptions, but not want to pay the performance penalty.
Set the NCURSES_NO_PADDING environment variable to disable all but mandatory padding.
Mandatory padding is used as a part of special control sequences such as flash.
NCURSES_NO_SETBUF
This setting is obsolete. Before changes
• started with 5.9 patch 20120825 and
• continued though 5.9 patch 20130126
ncurses enabled buffered output during terminal initialization. This was done (as in SVr4
curses) for performance reasons. For testing purposes, both of ncurses and certain
applications, this feature was made optional. Setting the NCURSES_NO_SETBUF variable
disabled output buffering, leaving the output in the original (usually line buffered)
mode.
In the current implementation, ncurses performs its own buffering and does not require
this workaround. It does not modify the buffering of the standard output.
The reason for the change was to make the behavior for interrupts and other signals more
robust. One drawback is that certain nonconventional programs would mix ordinary stdio(3)
calls with ncurses calls and (usually) work. This is no longer possible since ncurses is
not using the buffered standard output but its own output (to the same file descriptor).
As a special case, the low-level calls such as putp still use the standard output. But
high-level curses calls do not.
NCURSES_NO_UTF8_ACS
During initialization, the ncurses library checks for special cases where VT100 line-
drawing (and the corresponding alternate character set capabilities) described in the
terminfo are known to be missing. Specifically, when running in a UTF-8 locale, the Linux
console emulator and the GNU screen program ignore these. ncurses checks the TERM
environment variable for these. For other special cases, you should set this environment
variable. Doing this tells ncurses to use Unicode values which correspond to the VT100
line-drawing glyphs. That works for the special cases cited, and is likely to work for
terminal emulators.
When setting this variable, you should set it to a nonzero value. Setting it to zero (or
to a nonnumber) disables the special check for “linux” and “screen”.
As an alternative to the environment variable, ncurses checks for an extended terminfo
capability U8. This is a numeric capability which can be compiled using tic -x. For
example
# linux console, if patched to provide working
# VT100 shift-in/shift-out, with corresponding font.
linux-vt100|linux console with VT100 line-graphics,
U8#0, use=linux,
# uxterm with vt100Graphics resource set to false
xterm-utf8|xterm relying on UTF-8 line-graphics,
U8#1, use=xterm,
The name “U8” is chosen to be two characters, to permit it to be used by applications that
use ncurses' termcap interface.
NCURSES_TRACE
During initialization, the ncurses debugging library checks the NCURSES_TRACE environment
variable. If it is defined, to a numeric value, ncurses calls the trace function, using
that value as the argument.
The argument values, which are defined in curses.h, provide several types of information.
When running with traces enabled, your application will write the file trace to the
current directory.
See trace(3NCURSES) for more information.
TERM
Denotes your terminal type. Each terminal type is distinct, though many are similar.
TERM is commonly set by terminal emulators to help applications find a workable terminal
description. Some of those choose a popular approximation, e.g., “ansi”, “vt100”, “xterm”
rather than an exact fit. Not infrequently, your application will have problems with that
approach, e.g., incorrect function-key definitions.
If you set TERM in your environment, it has no effect on the operation of the terminal
emulator. It only affects the way applications work within the terminal. Likewise, as a
general rule (xterm(1) being a rare exception), terminal emulators which allow you to
specify TERM as a parameter or configuration value do not change their behavior to match
that setting.
TERMCAP
If the ncurses library has been configured with termcap support, ncurses will check for a
terminal's description in termcap form if it is not available in the terminfo database.
The TERMCAP environment variable contains either a terminal description (with newlines
stripped out), or a file name telling where the information denoted by the TERM
environment variable exists. In either case, setting it directs ncurses to ignore the
usual place for this information, e.g., /etc/termcap.
TERMINFO
ncurses can be configured to read from multiple terminal databases. The TERMINFO variable
overrides the location for the default terminal database. Terminal descriptions (in
terminal format) are stored in terminal databases:
• Normally these are stored in a directory tree, using subdirectories named by the first
letter of the terminal names therein.
This is the scheme used in System V, which legacy Unix systems use, and the TERMINFO
variable is used by curses applications on those systems to override the default
location of the terminal database.
• If ncurses is built to use hashed databases, then each entry in this list may be the
path of a hashed database file, e.g.,
/usr/share/terminfo.db
rather than
/usr/share/terminfo/
The hashed database uses less disk-space and is a little faster than the directory
tree. However, some applications assume the existence of the directory tree, reading
it directly rather than using the terminfo library calls.
• If ncurses is built with a support for reading termcap files directly, then an entry
in this list may be the path of a termcap file.
• If the TERMINFO variable begins with “hex:” or “b64:”, ncurses uses the remainder of
that variable as a compiled terminal description. You might produce the base64 format
using infocmp(1):
TERMINFO="$(infocmp -0 -Q2 -q)"
export TERMINFO
The compiled description is used if it corresponds to the terminal identified by the
TERM variable.
Setting TERMINFO is the simplest, but not the only way to set location of the default
terminal database. The complete list of database locations in order follows:
• the last terminal database to which ncurses wrote, if any, is searched first
• the location specified by the TERMINFO environment variable
• $HOME/.terminfo
• locations listed in the TERMINFO_DIRS environment variable
• one or more locations whose names are configured and compiled into the ncurses
library, i.e.,
• /etc/terminfo:/lib/terminfo:/usr/share/terminfo (corresponding to the
TERMINFO_DIRS variable)
• /etc/terminfo (corresponding to the TERMINFO variable)
TERMINFO_DIRS
Specifies a list of locations to search for terminal descriptions. Each location in the
list is a terminal database as described in the section on the TERMINFO variable. The
list is separated by colons (i.e., ":") on Unix, semicolons on OS/2 EMX.
There is no corresponding feature in System V terminfo; it is an extension developed for
ncurses.
TERMPATH
If TERMCAP does not hold a file name then ncurses checks the TERMPATH environment
variable. This is a list of filenames separated by spaces or colons (i.e., ":") on Unix,
semicolons on OS/2 EMX.
If the TERMPATH environment variable is not set, ncurses looks in the files
/etc/termcap, /usr/share/misc/termcap and $HOME/.termcap,
in that order.
The library may be configured to disregard the following variables when the current user
is the superuser (root), or if the application uses setuid or setgid permissions:
$TERMINFO, $TERMINFO_DIRS, $TERMPATH, as well as $HOME.
ALTERNATE CONFIGURATIONS
Many different ncurses configurations are possible, determined by the options given to the
configure script when building the library. Run the script with the --help option to
peruse them all. A few are of particular significance to the application developer
employing ncurses.
--disable-overwrite
The standard include for ncurses is as noted in SYNOPSIS:
#include <curses.h>
This option is used to avoid filename conflicts when ncurses is not the main
implementation of curses of the computer. If ncurses is installed disabling
overwrite, it puts its headers in a subdirectory, e.g.,
#include <ncurses/curses.h>
It also omits a symbolic link which would allow you to use -lcurses to build
executables.
--enable-widec
The configure script renames the library and (if the --disable-overwrite option is
used) puts the header files in a different subdirectory. All of the library names
have a “w” appended to them, i.e., instead of
-lncurses
you link with
-lncursesw
You must also enable the wide-character features in the header file when compiling
for the wide-character library to use the extended (wide-character) functions. The
symbol which enables these features has changed since XSI Curses, Issue 4:
• Originally, the wide-character feature required the symbol _XOPEN_SOURCE_EXTENDED
but that was only valid for XPG4 (1996).
• Later, that was deemed conflicting with _XOPEN_SOURCE defined to 500.
• As of mid-2018, none of the features in this implementation require a
_XOPEN_SOURCE feature greater than 600. However, X/Open Curses, Issue 7 (2009)
recommends defining it to 700.
• Alternatively, you can enable the feature by defining NCURSES_WIDECHAR with the
caveat that some other header file than curses.h may require a specific value for
_XOPEN_SOURCE (or a system-specific symbol).
The curses.h header file installed for the wide-character library is designed to be
compatible with the non-wide library's header. Only the size of the WINDOW structure
differs; few applications require more than pointers to WINDOWs.
If the headers are installed allowing overwrite, the wide-character library's headers
should be installed last, to allow applications to be built using either library from
the same set of headers.
--with-pthread
The configure script renames the library. All of the library names have a “t”
appended to them (before any “w” added by --enable-widec).
The global variables such as LINES are replaced by macros to allow read-only access.
At the same time, setter-functions are provided to set these values. Some
applications (very few) may require changes to work with this convention.
--with-shared
--with-normal
--with-debug
--with-profile
The shared and normal (static) library names differ by their suffixes, e.g.,
libncurses.so and libncurses.a. The debug and profiling libraries add a “_g” and a
“_p” to the root names respectively, e.g., libncurses_g.a and libncurses_p.a.
--with-termlib
Low-level functions which do not depend upon whether the library supports wide-
characters, are provided in the tinfo library.
By doing this, it is possible to share the tinfo library between wide/normal
configurations as well as reduce the size of the library when only low-level
functions are needed.
Those functions are described in these pages:
• extensions(3NCURSES) - miscellaneous curses extensions
• inopts(3NCURSES) - curses input options
• kernel(3NCURSES) - low-level curses routines
• termattrs(3NCURSES) - curses environment query routines
• termcap(3NCURSES) - curses emulation of termcap
• terminfo(3NCURSES) - curses interface to terminfo database
• util(3NCURSES) - miscellaneous curses utility routines
--with-trace
The trace function normally resides in the debug library, but it is sometimes useful
to configure this in the shared library. Configure scripts should check for the
function's existence rather than assuming it is always in the debug library.
FILES
/usr/share/tabset
tab stop initialization database
/etc/terminfo
compiled terminal capability database
NOTES
X/Open Curses permits most functions it specifies to be made available as macros as well.
ncurses does so
• for functions that return values via their parameters,
• to support obsolete features,
• to reuse functions (for example, those that move the cursor before another operation),
and
• a few special cases.
If the standard output file descriptor of an ncurses program is redirected to something
that is not a terminal device, the library writes screen updates to the standard error
file descriptor. This was an undocumented feature of SVr3.
See subsection “Header files” below regarding symbols exposed by inclusion of curses.h.
EXTENSIONS
ncurses enables an application to capture mouse events on certain terminals, including
xterm; see mouse(3NCURSES).
ncurses provides a means of responding to window resizing events, as when running in a GUI
terminal emulator application such as xterm; see resizeterm(3NCURSES) and
wresize(3NCURSES).
ncurses allows an application to query the terminal for the presence of a wide variety of
special keys; see has_key(3NCURSES).
ncurses extends the fixed set of function key capabilities specified by X/Open Curses by
allowing the application programmer to define additional key sequences at runtime; see
define_key(3NCURSES), key_defined(3NCURSES), and keyok(3NCURSES).
ncurses can exploit the capabilities of terminals implementing ISO 6429/ECMA-48 SGR 39 and
SGR 49 sequences, which allow an application to reset the terminal to its original
foreground and background colors. From a user's perspective, the application is able to
draw colored text on a background whose color is set independently, providing better
control over color contrasts. See default_colors(3NCURSES).
An ncurses application can choose to hide the internal details of WINDOW structures,
instead using accessor functions such as is_scrollok(3NCURSES).
ncurses enables an application to direct application output to a printer attached to the
terminal device; see print(3NCURSES).
ncurses offers slk_attr(3NCURSES) as a counterpart of attr_get(3NCURSES) for soft-label
key lines, and extended_slk_color(3NCURSES) as a form of slk_color(3NCURSES) that can
gather color information from them when many colors are supported.
Some extensions are only available if ncurses is compiled to support them; see section
“ALTERNATE CONFIGURATIONS” above.
• Rudimentary support for multi-threaded applications may be available; see
threads(3NCURSES).
• Functions that ease the management of multiple screens can be exposed; see
sp_funcs(3NCURSES).
• The compiler option -DUSE_GETCAP causes the library to fall back to reading
/etc/termcap if the terminal setup code cannot find a terminfo entry corresponding to
TERM. Use of this feature is not recommended, as it essentially includes an entire
termcap compiler in the ncurses startup code, at a cost in memory usage and
application launch latency.
PDCurses and NetBSD curses incorporate some ncurses extensions. Individual man pages
indicate where this is the case.
PORTABILITY
X/Open Curses defines two levels of conformance, “base” and “enhanced”. The latter
includes several additional features, such as wide-character and color support. ncurses
intends base-level conformance with X/Open Curses, and supports nearly all its enhanced
features.
Differences between X/Open Curses and ncurses are documented in the “PORTABILITY” sections
of applicable man pages.
Error Checking
In many cases, X/Open Curses is vague about error conditions, omitting some of the SVr4
documentation.
Unlike other implementations, this one checks parameters such as pointers to WINDOW
structures to ensure they are not null. The main reason for providing this behavior is to
guard against programmer error. The standard interface does not provide a way for the
library to tell an application which of several possible errors were detected. Relying on
this (or some other) extension will adversely affect the portability of curses
applications.
Padding Differences
In historic curses versions, delays embedded in the capabilities cr, ind, cub1, ff and tab
activated corresponding delay bits in the Unix tty driver. In this implementation, all
padding is done by sending NUL bytes. This method is slightly more expensive, but narrows
the interface to the Unix kernel significantly and increases the package's portability
correspondingly.
Header Files
The header file curses.h itself includes the header files stdio.h and unctrl.h.
X/Open Curses has more to say, but does not finish the story:
The inclusion of <curses.h> may make visible all symbols from the headers <stdio.h>,
<term.h>, <termios.h>, and <wchar.h>.
Here is a more complete story:
• Starting with BSD curses, all implementations have included <stdio.h>.
BSD curses included <curses.h> and <unctrl.h> from an internal header file curses.ext
(“ext” abbreviated “externs”).
BSD curses used <stdio.h> internally (for printw and scanw), but nothing in <curses.h>
itself relied upon <stdio.h>.
• SVr2 curses added newterm(3NCURSES), which relies upon <stdio.h>. That is, the
function prototype uses FILE.
SVr4 curses added putwin and getwin, which also use <stdio.h>.
X/Open Curses documents all three of these functions.
SVr4 curses and X/Open Curses do not require the developer to include <stdio.h> before
including <curses.h>. Both document curses showing <curses.h> as the only required
header.
As a result, standard <curses.h> will always include <stdio.h>.
• X/Open Curses is inconsistent with respect to SVr4 regarding <unctrl.h>.
As noted in util(3NCURSES), ncurses includes <unctrl.h> from <curses.h> (like SVr4).
• X/Open's comments about <term.h> and <termios.h> may refer to HP-UX and AIX:
HP-UX curses includes <term.h> from <curses.h> to declare setupterm in curses.h, but
ncurses (and Solaris curses) do not.
AIX curses includes <term.h> and <termios.h>. Again, ncurses (and Solaris curses) do
not.
• X/Open says that <curses.h> may include <term.h>, but there is no requirement that it
do that.
Some programs use functions declared in both <curses.h> and <term.h>, and must include
both headers in the same module. Very old versions of AIX curses required including
<curses.h> before including <term.h>.
Because ncurses header files include the headers needed to define datatypes used in
the headers, ncurses header files can be included in any order. But for portability,
you should include <curses.h> before <term.h>.
• X/Open Curses says "may make visible" because including a header file does not
necessarily make all symbols in it visible (there are ifdef's to consider).
For instance, in ncurses <wchar.h> may be included if the proper symbol is defined,
and if ncurses is configured for wide-character support. If the header is included,
its symbols may be made visible. That depends on the value used for _XOPEN_SOURCE
feature test macro.
• X/Open Curses documents one required header, in a special case: <stdarg.h> before
<curses.h> to prototype the vw_printw and vw_scanw functions (as well as the obsolete
the vwprintw and vwscanw functions). Each of those uses a va_list parameter.
The two obsolete functions were introduced in SVr3. The other functions were
introduced in X/Open Curses. In between, SVr4 curses provided for the possibility
that an application might include either <varargs.h> or <stdarg.h>. Initially, that
was done by using void* for the va_list parameter. Later, a special type (defined in
<stdio.h>) was introduced, to allow for compiler type-checking. That special type is
always available, because <stdio.h> is always included by <curses.h>.
None of the X/Open Curses implementations require an application to include <stdarg.h>
before <curses.h> because they either have allowed for a special type, or (like
ncurses) include <stdarg.h> directly to provide a portable interface.
AUTHORS
Zeyd M. Ben-Halim, Eric S. Raymond, Thomas E. Dickey. Based on pcurses by Pavel Curtis.
SEE ALSO
curses_variables(3NCURSES), terminfo(5), user_caps(5)