位运算与嵌入式编程

//The function need set corresponding bit int 0
#define BIT_MASK(bit_pos) (0x01<<(bit_pos))
int Bit_Reset(unsigned int* val, unsigned char pos)
{
if (pos >= sizeof(unsigned int) * 8)
{
return 0;
}
*val = (*val && ~BIT_MASK(pos));
return 1;
}

*val = (*val & ~BIT_MASK(pos));

#include<stdlib.h>
#include<iostream>

//The function need set corresponding bit int 0
#define BIT_MASK(bit_pos) (0x01<<(bit_pos))
int Bit_Reset(unsigned int* val, unsigned char pos)
{
if (pos >= sizeof(unsigned int) * 8)
{
return 0;
}
*val = (*val & ~BIT_MASK(pos));
return 1;
}
int main()
{
unsigned int x = 0xffffffff;
unsigned char y = 4;
Bit_Reset(&x, y);
std::cout<<std::hex<<x<<'\n';
system("pause");
return 0;
}

int i = (int)p;(p的定义为char *p)

int i = dynamic_cast<int>(p)

int i = static_cast<int>(p)

int i = const_cast<int>(p)

int i = reinterpret_cast<int>(p)