通过结构体成员获得结构体地址

#include <stdio.h> #include <stdlib.h> #include <string.h> #define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) #define container_of(ptr, type, member) ({ \      const typeof( ((type *)0)->member ) *__mptr = (ptr); \      (type *)( (char *)__mptr - offsetof(type,member) );}) struct example{ unsigned char ea; int eb; int ec; }; int main() {         struct example *example=malloc(sizeof(struct example));         memset(example,0,sizeof(struct example));         printf("%p\n",example);         printf("%p\n",&(example->ec));         printf("%p\n",(void *)offsetof(struct example,ec));         printf("%p\n",container_of(&(example->ec),struct example,ec));         free(example);         example=NULL;         return 0; }