不是所有控件有返回值，二叉树排序模块时出现问题，只printf了最小数据，应该怎么修改；

node sort_node(node* proot,FILE *p)
{

if (proot->pleft)
    return sort_node(proot->pleft,p);
fprintf_s(p,"%ld\n", proot->data);
printf_s("%ld\n", proot->data);
if (proot->pright)
    return sort_node(proot->pright,p);

}

node sort_node(node* proot,FILE *p)
{

if (proot->pleft)

    return sort_node(proot->pleft,p);
fprintf_s(p,"%ld\n", proot->data);
printf_s("%ld\n", proot->data);
if (proot->pright)
    return sort_node(proot->pright,p);

}