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Badd_wch P,



Manpage of curs_add_wch


Section: Miscellaneous Library Functions (3X)
Index Return to Main Contents


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  


#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 );


The add_wch, wadd_wch, mvadd_wch, and mvwadd_wch functions put the complex character wch into the given window at its current position, which is then advanced. These functions perform wrapping and special-character 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 cursor 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 specified 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 functionally 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 performance 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 correspond to the same VT100 line-drawing set as addch(3X).


WACS_BOARD0x2592 #board of squares
WACS_BTEE0x2534 +bottom tee
WACS_BULLET0x00b7 obullet
WACS_CKBOARD0x2592 :checker board (stipple)
WACS_DARROW0x2193 varrow pointing down
WACS_DEGREE0x00b0 'degree symbol
WACS_DIAMOND0x25c6 +diamond
WACS_GEQUAL0x2265 >greater-than-or-equal-to
WACS_HLINE0x2500 -horizontal line
WACS_LANTERN0x2603 #lantern symbol
WACS_LARROW0x2190 <arrow pointing left
WACS_LEQUAL0x2264 <less-than-or-equal-to
WACS_LLCORNER0x2514 +lower left-hand corner
WACS_LRCORNER0x2518 +lower right-hand corner
WACS_LTEE0x2524 +left tee
WACS_NEQUAL0x2260 !not-equal
WACS_PI0x03c0 *greek pi
WACS_PLMINUS0x00b1 #plus/minus
WACS_PLUS0x253c +plus
WACS_RARROW0x2192 >arrow pointing right
WACS_RTEE0x251c +right tee
WACS_S10x23ba -scan line 1
WACS_S30x23bb -scan line 3
WACS_S70x23bc -scan line 7
WACS_S90x23bd _scan line 9
WACS_STERLING0x00a3 fpound-sterling symbol
WACS_TTEE0x252c +top tee
WACS_UARROW0x2191 ^arrow pointing up
WACS_ULCORNER0x250c +upper left-hand corner
WACS_URCORNER0x2510 +upper right-hand corner
WACS_VLINE0x2502 |vertical line

The wide-character configuration of ncurses also defines symbols for thick- and double-lines:


WACS_T_LLCORNER0x2517+thick lower left corner
WACS_T_URCORNER0x2513+thick upper right corner
WACS_T_LRCORNER0x251b+thick lower right corner
WACS_T_LTEE0x252b+thick tee pointing right
WACS_T_RTEE0x2523+thick tee pointing left
WACS_T_BTEE0x253b+thick tee pointing up
WACS_T_TTEE0x2533+thick tee pointing down
WACS_T_HLINE0x2501-thick horizontal line
WACS_T_VLINE0x2503|thick vertical line
WACS_T_PLUS0x254b+thick large plus or crossover
WACS_D_ULCORNER0x2554+double upper left corner
WACS_D_LLCORNER0x255a+double lower left corner
WACS_D_URCORNER0x2557+double upper right corner
WACS_D_LRCORNER0x255d+double lower right corner
WACS_D_RTEE0x2563+double tee pointing left
WACS_D_LTEE0x2560+double tee pointing right
WACS_D_BTEE0x2569+double tee pointing up
WACS_D_TTEE0x2566+double tee pointing down
WACS_D_HLINE0x2550-double horizontal line
WACS_D_VLINE0x2551|double vertical line
WACS_D_PLUS0x256c+double large plus or crossover


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.  


Note that add_wch, mvadd_wch, mvwadd_wch, and echo_wchar may be macros.  


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 misdefined 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, providing new definitions which are not in the SVr4 implementations.  


curses(3X), curs_addch(3X), curs_attr(3X), curs_clear(3X), curs_outopts(3X), curs_refresh(3X), putwc(3)



Line Graphics

This document was created by man2html using the manual pages.
Time: 17:30:37 GMT, October 23, 2013

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