mvadd_wch
#define mvadd_wch(y,x,cp) (move(y,x)?ERR:add_wch(cp))
#define mvadd_wch(y, x, cp) (move(y, x) ? ((cp), ERR) : add_wch(cp))
#undef mvadd_wch
mvadd_wch(int y, int x, const cchar_t *cc)