结构体

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <string.h>

typedef struct Peo {
    int age;
    char name[32];
}peo;

void copy1(peo *obj1, peo *obj2)
{
    *obj1 = *obj2;//可以直接整体赋值
}

void copy2(peo *obj1, peo *obj2)
{
    obj1->age = obj2->age;//也可以单个赋值
    strcpy(obj1->name, obj2->name);
}
int main()
{
    peo a = {1,"xiaoming"};
    peo aa = a;//支持整体赋值，故后面指针解引用也可以整体赋值
    printf("%d %s
", aa.age, aa.name);

    peo aaa;
    copy2(&aaa, &a);
    printf("%d %s
", aaa.age, aaa.name);

}

模拟开辟内存二级结构体指针：

#define _CRT_SECURE_NO_WARNINGS
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
typedef struct Peo {
    int age;
    char *name;
}peo;

peo* test(peo** obj)
{
    *obj = (peo*)malloc(sizeof(peo));
    if (*obj == NULL)
        return NULL;
    else
    {
        (*obj)->age = 10;
        (*obj)->name = "xiaohong";
        return *obj;
    }
}

void myfree(peo* obj)
{
    if (obj != NULL)
    {
        free(obj);
        obj = NULL;
    }
}
int main()
{
    peo *p1=NULL;
    test(&p1);
    printf("%d %s
", p1->age, p1->name);
    myfree(p1);
}