在被调用函数中获取资源

Posted 2022-09-10 yu-weijie

#include <iostream>

using namespace std;

struct Teacher

char name[64];
int age;

;

//在被调用函数 获取资源
int getTeacher(Teacher **p)

if (p == NULL)

return - 1;

Teacher *tmp = NULL;
tmp = (Teacher*)malloc(sizeof(Teacher));
if (tmp == NULL)

return -2;

tmp->age = 20;
*p = tmp;

int getTeacher1(Teacher*& p)

//给p赋值，相当于给main函数中的pt赋值
p = (Teacher*)malloc(sizeof(Teacher));
if (p == NULL)

return -1;

p->age = 30;

void FreeTeacher(Teacher* tmp)

if (tmp == NULL)

return;

free(tmp);

void main()

Teacher *pt = NULL;
//C语言中的二级指针
getTeacher(&pt);
cout << "age:" << pt->age << endl;
FreeTeacher(pt);

//C++中的引用（指针引用）
getTeacher1(pt);
cout << "age:" << pt->age << endl;
FreeTeacher(pt);
system("pause");