ResbufPointer类

class ResbufPointer {
        resbuf* pHead; // Maintain a pointer to the head of the resource chain for de-allocation
        resbuf* pBuffer;
public:
        ResbufPointer(resbuf* ptr) : pHead(ptr), pBuffer(ptr) {}
        ~ResbufPointer() {
                acutRelRb(pHead); // release the buffer
                pHead = pBuffer = 0;
        }
        resbuf* operator->() { return pBuffer; }  // so you can do things like buf->resval.rstring
        operator resbuf*() { return pBuffer; } // so you can pass the smart pointer to functions that expect a resbuf*
        bool isNull() { return pBuffer == 0; } // null pointer check
        void start() { pBuffer = pHead; } // in case you need to return to the head of the resource chain
        void next() { pBuffer = pBuffer->rbnext; } // try to move the pointer to the next item in the resource chain
};