类型转化，网络开发中常见的类型转化

#include <stdio.h>
#pragma pack(push,1)
struct A{
unsigned char b;
unsigned long a[3];
};
#pragma pack(push)
int main(){
A m;
m.a[0]=0xAABB;
m.a[1]=0xCCDD;
m.a[2]=0xEEFF;
m.b='Z';
int sizes=sizeof(m);
//把结构体转化成char*
char* change=(char*)&m;
// 把char* 转换成结构体

A* bb=(A*)(&(*change));
printf("%X\n",bb->a[0]);
printf("%X\n",bb->a[1]);
printf("%X\n",bb->a[2]);
printf("%c",bb->b);
return 0;
}