if (!cfg.scrollbar) return;
void set_sbar(int total, int start, int page){    inst->sbar_adjust->lower = 0;    inst->sbar_adjust->upper = total;    inst->sbar_adjust->value = start;    inst->sbar_adjust->page_size = page;    inst->sbar_adjust->step_increment = 1;    inst->sbar_adjust->page_increment = page/2;    inst->ignore_sbar = TRUE;    gtk_adjustment_changed(inst->sbar_adjust);    inst->ignore_sbar = FALSE;}