curs_add_wch(3X)curs_add_wch(3X)NAME
add_wch, wadd_wch, mvadd_wch, mvwadd_wch, echo_wchar, wecho_wchar - add
a complex character and rendition to a curses window, then advance the
cursor
SYNOPSIS
#include <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 );
DESCRIPTION
The add_wch, wadd_wch, mvadd_wch, and mvwadd_wch functions put the com‐
plex character wch into the given window at its current position, which
is then advanced. These functions perform wrapping and special-charac‐
ter processing as follows:
· If wch refers to a spacing character, then any previous character
at that location is removed. A new character specified by wch is
placed at that location with rendition specified by wch. The cur‐
sor then advances to the next spacing character on the screen.
· If wch refers to a non-spacing character, all previous characters
at that location are preserved. The non-spacing characters of wch
are added to the spacing complex character, and the rendition spec‐
ified by wch is ignored.
· If the character part of wch is a tab, newline, backspace or other
control character, the window is updated and the cursor moves as if
addch were called.
The echo_wchar function is functionally equivalent to a call to add_wch
followed by a call to refresh. Similarly, the wecho_wchar is function‐
ally equivalent to a call to wadd_wch followed by a call to wrefresh.
The knowledge that only a single character is being output is taken
into consideration and, for non-control characters, a considerable per‐
formance gain might be seen by using the *echo* functions instead of
their equivalents.
Line Graphics
Like addch(3X), addch_wch accepts symbols which make it simple to draw
lines and other frequently used special characters. These symbols cor‐
respond to the same VT100 line-drawing set as addch(3X).
Name Unicode Default Description
────────────────────────────────────────────────────────────────
WACS_BLOCK 0x25ae # solid square block
WACS_BOARD 0x2592 # board of squares
WACS_BTEE 0x2534 + bottom tee
WACS_BULLET 0x00b7 o bullet
WACS_CKBOARD 0x2592 : checker board (stipple)
WACS_DARROW 0x2193 v arrow pointing down
WACS_DEGREE 0x00b0 ' degree symbol
WACS_DIAMOND 0x25c6 + diamond
WACS_GEQUAL 0x2265 > greater-than-or-equal-to
WACS_HLINE 0x2500 - horizontal line
WACS_LANTERN 0x2603 # lantern symbol
WACS_LARROW 0x2190 < arrow pointing left
WACS_LEQUAL 0x2264 < less-than-or-equal-to
WACS_LLCORNER 0x2514 + lower left-hand corner
WACS_LRCORNER 0x2518 + lower right-hand corner
WACS_LTEE 0x2524 + left tee
WACS_NEQUAL 0x2260 ! not-equal
WACS_PI 0x03c0 * greek pi
WACS_PLMINUS 0x00b1 # plus/minus
WACS_PLUS 0x253c + plus
WACS_RARROW 0x2192 > arrow pointing right
WACS_RTEE 0x251c + right tee
WACS_S1 0x23ba - scan line 1
WACS_S3 0x23bb - scan line 3
WACS_S7 0x23bc - scan line 7
WACS_S9 0x23bd _ scan line 9
WACS_STERLING 0x00a3 f pound-sterling symbol
WACS_TTEE 0x252c + top tee
WACS_UARROW 0x2191 ^ arrow pointing up
WACS_ULCORNER 0x250c + upper left-hand corner
WACS_URCORNER 0x2510 + upper right-hand corner
WACS_VLINE 0x2502 | vertical line
The wide-character configuration of ncurses also defines symbols for
thick- and double-lines:
Name Unicode Default Description
─────────────────────────────────────────────────────────────────────
WACS_T_ULCORNER 0x250f + thick upper left corner
WACS_T_LLCORNER 0x2517 + thick lower left corner
WACS_T_URCORNER 0x2513 + thick upper right corner
WACS_T_LRCORNER 0x251b + thick lower right corner
WACS_T_LTEE 0x252b + thick tee pointing right
WACS_T_RTEE 0x2523 + thick tee pointing left
WACS_T_BTEE 0x253b + thick tee pointing up
WACS_T_TTEE 0x2533 + thick tee pointing down
WACS_T_HLINE 0x2501 - thick horizontal line
WACS_T_VLINE 0x2503 | thick vertical line
WACS_T_PLUS 0x254b + thick large plus or crossover
WACS_D_ULCORNER 0x2554 + double upper left corner
WACS_D_LLCORNER 0x255a + double lower left corner
WACS_D_URCORNER 0x2557 + double upper right corner
WACS_D_LRCORNER 0x255d + double lower right corner
WACS_D_RTEE 0x2563 + double tee pointing left
WACS_D_LTEE 0x2560 + double tee pointing right
WACS_D_BTEE 0x2569 + double tee pointing up
WACS_D_TTEE 0x2566 + double tee pointing down
WACS_D_HLINE 0x2550 - double horizontal line
WACS_D_VLINE 0x2551 | double vertical line
WACS_D_PLUS 0x256c + double large plus or crossover
RETURN VALUES
All routines return the integer ERR upon failure and OK on success.
Functions with a "mv" prefix first perform a cursor movement using
wmove, and return an error if the position is outside the window, or if
the window pointer is null.
NOTES
Note that add_wch, mvadd_wch, mvwadd_wch, and echo_wchar may be macros.
PORTABILITY
All of these functions are described in the XSI Curses standard, Issue
4. The defaults specified for line-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.
· HPUX curses equates some of the ACS_ symbols to the analogous WACS_
symbols as if the ACS_ symbols were wide characters. The misde‐
fined symbols are the arrows and other symbols which are not used
for line-drawing.
X/Open Curses does not define symbols for thick- or double-lines. SVr4
curses implementations defined their line-drawing symbols in terms of
intermediate symbols. This implementation extends those symbols, pro‐
viding new definitions which are not in the SVr4 implementations.
SEE ALSOcurses(3X), curs_addch(3X), curs_attr(3X), curs_clear(3X), curs_out‐
opts(3X), curs_refresh(3X), putwc(3)curs_add_wch(3X)
