http://www.cnblogs.com/zhanggaofeng/p/5421804.html
C语言中的深拷贝和浅拷贝
//C语言中的深拷贝和浅拷贝 #define _CRT_SECURE_NO_WARNINGS #include<stdio.h> #include<stdlib.h> #include<string.h>typedef struct _student{char name[30];char *title;int age; }Student;void main(){Student s1;Student s2;s1.age = 12;strcpy(s1.name, "小明");s1.title = (char *)malloc(sizeof(char)* 30);strcpy(s1.title, "总经理");s2 = s1;printf("s1的age=%d,s1的name=%s,s1的title=%s\n", s1.age, s1.name, s1.title);printf("s2的age=%d,s2的name=%s,s2的title=%s\n", s2.age, s2.name, s2.title);printf("s1的地址%x\n", s1.title); //打印b71408printf("s2的地址%x\n", s2.title); //打印b71408printf("s1的地址%x\n", s1.name); //打印d5fd18printf("s2的地址%x\n", s2.name); //打印d5fce8//这说明s1和s2中成员char *title;只是浅拷贝,两个指针指向同一块堆内存,//当释放free(s1.title);时,s2.title指向的内存空间也没释放了,所以再次释放会报错if (s1.title != NULL){free(s1.title);}//错误代码/*if (s2.title != NULL){free(s2.title);}*///要想实现深拷贝,那么必须给s2.title也分配一段内存空间,//然后通过strcpy()将s2.title指向的字符串复制到s2.title指向的内存空间内//由此证明,结构体之间的赋值(s2 = s1;),是进行了结构体内部所有数据的拷贝,//如上s1.name的地址s2.name的地址不同,说明是把s1.name中的数据复制到了s2.name中system("pause"); }