#include <curses.h>int bkgrnd(const cchar_t *wch);
void bkgrndset(const cchar_t *wch);
int getbkgrnd(cchar_t *wch);
int wbkgrnd(WINDOW *win, const cchar_t *wch);
void wbkgrndset(WINDOW *win, const cchar_t *wch);
int wgetbkgrnd(WINDOW *win, cchar_t *wch);
The bkgrnd(3curses) and wbkgrnd(3curses) functions turn off the previous background attributes, OR the requested attributes into the window rendition, and set the background property of the current or specified window and then apply this setting to every character position in that window:
If wch refers to a non-spacing complex character for bkgrnd(3curses), bkgrndset(3curses), wbkgrnd(3curses) and wbkgrndset(3curses), then wch is added to the existing spacing complex character that is the background character. If wch refers to a multi-column character, the results are unspecified.
The getbkgrnd(3curses) and wgetbkgrnd(3curses) functions store, into the area pointed to by wch, the value of the window's background character and rendition.
Upon successful completion, the other functions return OK. Otherwise, they return ERR.