svcadm(8)을 검색하려면 섹션에서 8 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.
add_wch(3x)
curs_add_wch(3x) Library calls curs_add_wch(3x)
NAME
add_wch, wadd_wch, mvadd_wch, mvwadd_wch, echo_wchar, wecho_wchar - add
a curses complex character to a window, possibly advancing the cursor
SYNOPSIS
#include <ncursesw/curses.h>
int add_wch(const cchar_t * wch);
int wadd_wch(WINDOW * win, const cchar_t * wch);
int mvadd_wch(int y, int x, const cchar_t * wch);
int mvwadd_wch(WINDOW * win, int y, int x,
const cchar_t * wch);
int echo_wchar(const cchar_t * wch);
int wecho_wchar(WINDOW * win, const cchar_t *wch);
/* (integer) constants */
/* ... */ WACS_BLOCK;
/* ... */ WACS_BOARD;
/* ... */ WACS_BTEE;
/* ... */ WACS_BULLET;
/* ... */ WACS_CKBOARD;
/* ... */ WACS_DARROW;
/* ... */ WACS_DEGREE;
/* ... */ WACS_DIAMOND;
/* ... */ WACS_HLINE;
/* ... */ WACS_LANTERN;
/* ... */ WACS_LARROW;
/* ... */ WACS_LLCORNER;
/* ... */ WACS_LRCORNER;
/* ... */ WACS_LTEE;
/* ... */ WACS_PLMINUS;
/* ... */ WACS_PLUS;
/* ... */ WACS_RARROW;
/* ... */ WACS_RTEE;
/* ... */ WACS_S1;
/* ... */ WACS_S9;
/* ... */ WACS_TTEE;
/* ... */ WACS_UARROW;
/* ... */ WACS_ULCORNER;
/* ... */ WACS_URCORNER;
/* ... */ WACS_VLINE;
/* extensions */
/* ... */ WACS_GEQUAL;
/* ... */ WACS_LEQUAL;
/* ... */ WACS_NEQUAL;
/* ... */ WACS_PI;
/* ... */ WACS_S3;
/* ... */ WACS_S7;
/* ... */ WACS_STERLING;
/* extensions for thick lines */
/* ... */ WACS_T_BTEE;
/* ... */ WACS_T_HLINE;
/* ... */ WACS_T_LLCORNER;
/* ... */ WACS_T_LRCORNER;
/* ... */ WACS_T_LTEE;
/* ... */ WACS_T_PLUS;
/* ... */ WACS_T_RTEE;
/* ... */ WACS_T_TTEE;
/* ... */ WACS_T_ULCORNER;
/* ... */ WACS_T_URCORNER;
/* ... */ WACS_T_VLINE;
/* extensions for double lines */
/* ... */ WACS_D_BTEE;
/* ... */ WACS_D_HLINE;
/* ... */ WACS_D_LLCORNER;
/* ... */ WACS_D_LRCORNER;
/* ... */ WACS_D_LTEE;
/* ... */ WACS_D_PLUS;
/* ... */ WACS_D_RTEE;
/* ... */ WACS_D_TTEE;
/* ... */ WACS_D_ULCORNER;
/* ... */ WACS_D_URCORNER;
/* ... */ WACS_D_VLINE;
DESCRIPTION
wadd_wch
wadd_wch writes the curses complex character wch to the window win,
then may advance the cursor position, analogously to the standard C li‐
brary's putwchar(3). ncurses(3X) describes the variants of this func‐
tion.
Construct a curses complex character from a wchar_t with setcchar(3X).
A cchar_t can be copied from place to place using win_wch(3X) and
wadd_wch. See curs_attr(3X) for values of predefined constants that
can be usefully “or”ed with characters. A complex character whose only
character component is a wide space, and whose only attribute is
WA_NORMAL, is a blank character, and therefore combines with the win‐
dow's background character; see curs_bkgrnd(3X).
Much behavior depends on whether the wide characters in wch are spacing
or non-spacing; see subsection “Complex Characters” below.
• If wch contains a spacing character, then any character at the cur‐
sor is first removed. The complex character wch, with its attrib‐
utes and color pair identifier, becomes the base of the active com‐
plex character.
• If wch contains only non-spacing characters, they are combined with
the active complex character. curses ignores its attributes and
color pair identifier, and does not advance the cursor.
Further non-spacing characters added with wadd_wch are not written at
the new cursor position but combine with the active complex character
until another spacing character is written to the window or the cursor
is moved.
If wch is a backspace, carriage return, line feed, or tab, the cursor
moves appropriately within the window.
• Backspace moves the cursor one character left; at the left margin
of a window, it does nothing.
• Carriage return moves the cursor to the left margin on the same
line of the window.
• Line feed does a clrtoeol(3X), then advances as if from the right
margin.
• Tab advances the cursor to the next tab stop (possibly on the next
line); these are placed at every eighth column by default.
Alter the tab interval with the TABSIZE extension; see
curs_variables(3X).
If wch is any other nonprintable character, it is drawn in printable
form using the same convention as wunctrl(3X). Calling win_wch(3X) on
the location of a nonprintable character does not return the character
itself, but its wunctrl(3X) representation.
Adding spacing characters with wadd_wch causes it to wrap at the right
margin of the window:
• If the cursor is not at the bottom of the scrolling region and ad‐
vancement occurs at the right margin, the cursor automatically
wraps to the beginning of the next line.
• If the cursor is at the bottom of the scrolling region when ad‐
vancement occurs at the right margin, and scrollok(3X) is enabled
for win, the scrolling region scrolls up one line and the cursor
wraps as above. Otherwise, advancement and scrolling do not occur,
and wadd_wch returns ERR.
A window's margins may coincide with the screen boundaries. This may
be a problem when ncurses updates the screen to match the curses win‐
dow. When their right and bottom margins coincide, ncurses uses dif‐
ferent strategies to handle the variations of scrolling and wrapping at
the lower-right corner by depending on the terminal capabilities:
• If the terminal does not automatically wrap as characters are added
at the right margin (i.e., auto right margins), ncurses writes the
character directly.
• If the terminal has auto right margins, but also has capabilities
for turning auto margins off and on, ncurses turns the auto margin
feature off temporarily when writing to the lower-right corner.
• If the terminal has an insertion mode which can be turned off and
on, ncurses writes the character just before the lower-right cor‐
ner, and then inserts a character to push the update into the cor‐
ner.
wecho_wchar
echo_wchar and wecho_wchar are equivalent to calling (w)add_wch fol‐
lowed by (w)refresh on stdscr or the specified window. curses inter‐
prets these functions as a hint that only a single (complex) character
is being output; for non-control characters, a considerable performance
gain may be enjoyed by employing them.
Forms-Drawing Characters
curses defines macros starting with WACS_ that can be used with
wadd_wch to write line-drawing and other symbols to the screen.
ncurses terms these forms-drawing characters. curses uses the ACS de‐
fault listed below if the terminal type lacks the acs_chars (acsc) ca‐
pability; that capability does not define a replacement for the charac‐
ter; or if the terminal type and locale configuration require Unicode
to access these characters, but the library is unable to use Unicode.
The “acsc char” column corresponds to how the characters are specified
in the acs_chars (acsc) string capability, and the characters in it may
appear on the screen if the terminal type's database entry incorrectly
advertises ACS support. The name “ACS” originates in the Alternate
Character Set feature of the DEC VT100 terminal.
Lb Lb Lb Lb Lb Lb Lb Lb Lb Lb Lb L L L Lx. Uni‐
code ACS acsc Symbol Default Default char Glyph Name _
WACS_BLOCK U+25ae # 0 T{ solid square block T}
WACS_BOARD U+2592 # h board of squares
WACS_BTEE U+2534 + v bottom tee WACS_BUL‐
LET U+00b7 o ~ bullet WACS_CKBOARD U+2592 : a T{
checker board (stipple) T} WACS_DARROW U+2193 v . T{ arrow
pointing down T} WACS_DEGREE U+00b0 ' f degree symbol
WACS_DIAMOND U+25c6 + ` diamond
WACS_GEQUAL U+2265 > > T{ greater-than-or-equal-to T}
WACS_HLINE U+2500 - q horizontal line
WACS_LANTERN U+2603 # i lantern symbol WACS_LAR‐
ROW U+2190 < , T{ arrow pointing left T}
WACS_LEQUAL U+2264 < y T{ less-than-or-equal-to T} WACS_LL‐
CORNER U+2514 + m T{ lower left-hand corner T} WACS_LR‐
CORNER U+2518 + j T{ lower right-hand corner T}
WACS_LTEE U+2524 + t left tee
WACS_NEQUAL U+2260 ! | not-equal
WACS_PI U+03c0 * { greek pi WACS_PLMI‐
NUS U+00b1 # g plus/minus WACS_PLUS U+253c + n plus
WACS_RARROW U+2192 > + T{ arrow pointing right T}
WACS_RTEE U+251c + u right tee
WACS_S1 U+23ba - o scan line 1
WACS_S3 U+23bb - p scan line 3
WACS_S7 U+23bc - r scan line 7
WACS_S9 U+23bd _ s scan line 9 WACS_STER‐
LING U+00a3 f } T{ pound-sterling symbol T}
WACS_TTEE U+252c + w top tee WACS_UARROW U+2191
^ - T{ arrow pointing up T} WACS_UL‐
CORNER U+250c + l T{ upper left-hand corner T} WACS_UR‐
CORNER U+2510 + k T{ upper right-hand corner T}
WACS_VLINE U+2502 | x vertical line
The ncurses wide API also defines symbols for thick lines (acsc “J”
through “N”, “T” through “X”, and “Q”):
Lb Lb Lb Lb Lb Lb Lb Lb Lb Lb Lb L L L Lx. Uni‐
code ASCII acsc ACS Name Default Default Char Glyph Name _
WACS_T_BTEE U+253b + V T{ thick tee pointing up T}
WACS_T_HLINE U+2501 - Q T{ thick horizontal line T}
WACS_T_LLCORNER U+2517 + M T{ thick lower left corner T}
WACS_T_LRCORNER U+251b + J T{ thick lower right corner T}
WACS_T_LTEE U+252b + T T{ thick tee pointing right T}
WACS_T_PLUS U+254b + N T{ thick large plus T}
WACS_T_RTEE U+2523 + U T{ thick tee pointing left T}
WACS_T_TTEE U+2533 + W T{ thick tee pointing down T}
WACS_T_ULCORNER U+250f + L T{ thick upper left corner T}
WACS_T_URCORNER U+2513 + K T{ thick upper right corner T}
WACS_T_VLINE U+2503 | X T{ thick vertical line T}
and for double lines (acsc “A” through “I”, plus “R” and “Y”):
Lb Lb Lb Lb Lb Lb Lb Lb Lb Lb Lb L L L Lx. Uni‐
code ASCII acsc ACS Name Default Default Char Glyph Name _
WACS_D_BTEE U+2569 + H T{ double tee pointing up T}
WACS_D_HLINE U+2550 - R T{ double horizontal line T}
WACS_D_LLCORNER U+255a + D T{ double lower left corner T}
WACS_D_LRCORNER U+255d + A T{ double lower right corner T}
WACS_D_LTEE U+2560 + F T{ double tee pointing right T}
WACS_D_PLUS U+256c + E T{ double large plus T}
WACS_D_RTEE U+2563 + G T{ double tee pointing left T}
WACS_D_TTEE U+2566 + I T{ double tee pointing down T}
WACS_D_ULCORNER U+2554 + C T{ double upper left corner T}
WACS_D_URCORNER U+2557 + B T{ double upper right corner T}
WACS_D_VLINE U+2551 | Y T{ double vertical line T}
Unicode's descriptions for these characters differs slightly from
ncurses, by introducing the term “light” (along with less important de‐
tails). Here are its descriptions for the normal, thick, and double
horizontal lines:
• U+2500 BOX DRAWINGS LIGHT HORIZONTAL
• U+2501 BOX DRAWINGS HEAVY HORIZONTAL
• U+2550 BOX DRAWINGS DOUBLE HORIZONTAL
RETURN VALUE
These functions return OK on success and ERR on failure.
In ncurses, these functions fail if
• the curses screen has not been initialized,
• (for functions taking a WINDOW pointer argument) win is a null
pointer,
• wrapping to a new line is impossible because scrollok(3X) has not
been called on win (or stdscr, as applicable) when writing to its
bottom right location is attempted, or
• it is not possible to add a complete character at the cursor posi‐
tion.
Functions prefixed with “mv” first perform cursor movement and fail if
the position (y, x) is outside the window boundaries.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
box; cbp-1 | cbp-1 l | l . ATTRIBUTE TYPE ATTRIBUTE VALUE = Availabil‐
ity library/ncurses = Stability Uncommitted
NOTES
add_wch, mvadd_wch, mvwadd_wch, and echo_wchar may be implemented as
macros.
Source code for open source software components in Oracle Solaris can
be found at https://www.oracle.com/downloads/opensource/solaris-source-
code-downloads.html.
This software was built from source available at:
https://github.com/oracle/solaris-userland
The original community source was downloaded from:
https://invisible-mirror.net/archives/ncurses/cur‐
rent/ncurses-6.5-20250614.tgz
Further information about this software can be found on the open source
community website at https://invisible-island.net/ncurses/.
EXTENSIONS
The symbols WACS_S3, WACS_S7, WACS_LEQUAL, WACS_GEQUAL, WACS_PI,
WACS_NEQUAL, and WACS_STERLING are not standard. However, many pub‐
licly available terminfo entries include acs_chars (acsc) capabilities
in which their key characters (pryz{|}) are embedded, and a second-hand
list of their character descriptions has come to light. The ncurses
developers invented WACS-prefixed names for them.
PORTABILITY
Applications employing ncurses extensions should condition their use on
the visibility of the NCURSES_VERSION preprocessor macro.
These functions are described in X/Open Curses Issue 4. It specifies
no error conditions for them.
The defaults specified for forms-drawing characters apply in the POSIX
locale. X/Open Curses makes it clear that the WACS_ symbols should be
defined as a pointer to cchar_t data, e.g., in the discussion of
border_set. A few implementations are problematic:
• NetBSD curses defines the symbols as a wchar_t within a cchar_t.
• HP-UX curses equates some of the ACS_ symbols to the analogous
WACS_ symbols as if the ACS_ symbols were wide characters. The
misdefined symbols are the arrows and other symbols which are not
used for line-drawing.
X/Open Curses does not specify symbols for thick- or double-lines.
SVr4 curses implementations defined their line-drawing symbols in terms
of intermediate symbols. ncurses extends those symbols, providing new
definitions not found in SVr4 implementations.
Not all Unicode-capable terminals provide support for VT100-style al‐
ternate character sets (i.e., the acsc_chars (acsc) capability), with
their corresponding line-drawing characters. X/Open Curses did not ad‐
dress the aspect of integrating Unicode with line-drawing characters.
Existing implementations of System V curses (AIX, HP-UX, Solaris) use
only the acsc_chars (acsc) character-mapping to provide this feature.
As a result, those implementations can use only single-byte line-draw‐
ing characters. ncurses 5.3 (2002) provided a table of Unicode values
to solve these problems. NetBSD curses incorporated that table in
2010.
ncurses uses the Unicode values instead of the terminal type descrip‐
tion's acsc_chars (acsc) mapping as discussed in ncurses(3X) for the
environment variable NCURSES_NO_UTF8_ACS. In contrast, for the same
cases, the line-drawing characters described in addch(3X) will use only
the ASCII default values.
Having Unicode available does not solve all of the problems with line-
drawing for curses:
• The closest Unicode equivalents to the VT100 graphics S1, S3, S7,
and S9 frequently are not displayed at the regular intervals which
the terminal used.
• The lantern is a special case. It originated with the AT&T 4410
terminal in the early 1980s. There is no accessible documentation
depicting the lantern symbol on the AT&T terminal.
Lacking documentation, most readers assume that a storm lantern was
intended. But there are several possibilities, all with problems.
Unicode 6.0 (2010) does provide two lantern symbols: U+1F383 and
U+1F3EE. Those were not available in 2002, and are irrelevant
since they lie outside the Basic Multilingual Plane and as a result
are unavailable on many terminals. They are not storm lanterns, in
any case.
Most storm lanterns have a tapering glass chimney (to guard against
tipping); some have a wire grid protecting the chimney.
For the tapering appearance, ☃ U+2603 was adequate. In use on a
terminal, no one can tell what the image represents. Unicode calls
it a snowman.
Others have suggested these alternatives: § U+00A7 (section mark),
Θ U+0398 (theta), Φ U+03A6 (phi), δ U+03B4 (delta), ⌧ U+2327 (x in
a rectangle), ╬ U+256C (forms double vertical and horizontal), and
☒ U+2612 (ballot box with x).
Complex Characters
The complex character type cchar_t can store more than one wide charac‐
ter (wchar_t). X/Open Curses does not mention this possibility, speci‐
fying behavior only where wch is a single character, either spacing or
non-spacing.
ncurses assumes that wch is constructed using setcchar(3X), and in turn
that the result
• contains at most one spacing character at the beginning of its list
of wide characters, and zero or more non-spacing characters, or
• holds one non-spacing character.
In the latter case, ncurses adds the non-spacing character to the ac‐
tive complex character.
HISTORY
X/Open Curses Issue 4 (1995) initially specified these functions. The
System V Interface Definition (SVID) Version 4 of the same year speci‐
fied functions named waddwch (and the usual variants), echowchar, and
wechowchar. These were later additions to SVr4.x, not appearing in the
first SVr4 (1989). They differed from X/Open's later wadd_wch and
wecho_wchar in that they each took an argument of type wchar_t instead
of cchar_t. SVID defined no WACS_ symbols.
X/Open Curses Issue 4 also defined many of the WACS_ constants, except‐
ing WACS_GEQUAL, WACS_LEQUAL, WACS_NEQUAL, WACS_PI, WACS_S3, WACS_S7,
and WACS_STERLING; and those for drawing thick and double lines.
ncurses 5.3 (2002) furnished the remaining WACS_ constants.
SEE ALSO
curs_addch(3X) describes comparable functions of the ncurses library in
its non-wide-character configuration.
curses(3X), curs_addwstr(3X), curs_add_wchstr(3X), curs_attr(3X),
curs_bkgrnd(3X), curs_clear(3X), curs_getcchar(3X), curs_outopts(3X),
curs_refresh(3X), curs_variables(3X), putwc(3)
ncurses 6.5 2025-04-19 curs_add_wch(3x)