指针的指针作为形参实测
1. VS2019里面创建C++控制台工程
2. 代码
#include <iostream>uint8_t buf[3][10] = { {1,2,3},{4,5,6,7,8},{9,0} };
uint8_t len1 = 3,len2 = 5,len3 = 2;void f1(uint8_t **dstBuf, uint8_t *dstLen)
{*dstBuf = buf[0];*dstLen = len1;
}void f2(uint8_t** dstBuf, uint8_t* dstLen)
{*dstBuf = buf[1];*dstLen = len2;
}void f3(uint8_t** dstBuf, uint8_t* dstLen)
{*dstBuf = buf[2];*dstLen = len3;
}void print_f(uint8_t* buf, uint8_t len)
{for (int i = 0;i < len;i++){printf("%d ",buf[i]);}printf("\n");
}int main()
{uint8_t *rxBuf,rxLen;std::cout << "Hello World!\n";f1(&rxBuf, &rxLen);printf("f1:");print_f(rxBuf, rxLen);f2(&rxBuf, &rxLen);printf("f2:");print_f(rxBuf, rxLen);f3(&rxBuf, &rxLen);printf("f3:");print_f(rxBuf, rxLen);int i = 3;int* p;p = &i;int** q;q = &p;printf("%d", **q);}
rxBuf的地址&rxBuf = 0x00dff978 作为形参传入f1（）
这样dstBuf = &rxBuf = 0x00dff978
*dstBuf = 0x0013c000 就是buf[0]的地址
rxBuf通过调用函数，在函数中修改指针的值，达到指向不同缓存数组的目的。
3. 效果
