64位机器的地址操作

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <inttypes.h>

struct s1 {
    int a;
    char *c;
};

void main()
{
    char t='a';
    struct s1 *u=malloc(sizeof(struct s1));

    printf("size of s1: %d\n", sizeof(struct s1));
    printf("%p,%p\n",u, u->c);

    u->c=&t;

    printf("%p,%p: %lx, %c\n",u, u->c, *((uint64_t *) ((char *)u + 8)), *(u->c));
    printf("%p\n", &(u->c));

    free(u);
    return;
}

输出结果：

size of s1: 16
0x2018010,(nil)
0x2018010,0x7fff1060b0a7: 7fff1060b0a7, a
0x2018018