How to determine if a buffer is freed or not

Question

I use new to allocate a buffer, as follows:

    BYTE *p;

    p = new BYTE[20];


    ...

    delete p;

After p is deleted, if I do NOT assign NULL to p , is there a way to determine whether it has already been freed?

Answer 1

您无法确定这一点，这是您通常依赖于高级机制来处理内存的主要原因之一，例如智能指针（ shared_ptr ， unique_ptr等），或者在您的情况下使用std::vector进行处理原始内存，以确保不会因未定义行为启动程序的两次delete ，忘记delete或其他令人讨厌的错误。