man:add_wch(3ncurses)

add_wch(3NCURSES) add_wch(3NCURSES) 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 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(3NCURSES) 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. RETURN VALUES All routines return the integer ERR upon failure and OK on success. NOTES Note that add_wch, mvadd_wch, mvwadd_wch, and echo_wchar may be macros. PORTABILITY All these functions are described in the XSI Curses standard, Issue 4. The defaults specified for forms-drawing characters apply in the POSIX locale. XSI documents constants beginning with WACS_ which are used for line- drawing. Those are not currently implemented in ncurses. SEE ALSO ncurses(3NCURSES), attr_get(3NCURSES), clear(3NCURSES), out- opts(3NCURSES), refresh(3NCURSES), putwc(3) add_wch(3NCURSES)