zx_fillrect
void zx_fillrect(struct rasops_info *, int, int, int, int, uint32_t, int);
zx_fillrect(ri, ri->ri_ccol, ri->ri_crow, 1, 1, WSCOL_BLACK << 16,
zx_fillrect(ri, col, row, num, 1, attr, ZX_STD_ROP);
zx_fillrect(ri, 0, row, ri->ri_cols, num, attr, ZX_STD_ROP);
zx_fillrect(ri, col, row, 1, 1, attr, ZX_STD_ROP);