screen_write_clearcharacter
screen_write_clearcharacter(sctx, n, bg);
screen_write_clearcharacter(ctx, w, gc->bg);
screen_write_clearcharacter(ctx, aw, sy.fill);
void screen_write_clearcharacter(struct screen_write_ctx *, u_int, u_int);
screen_write_clearcharacter(&ctx, box_w - 2, gc.bg);
screen_write_clearcharacter(&ctx, box_w - 2, gc.bg);
screen_write_clearcharacter(ctx, width + 2, border_gc->bg);