/*跨函数使用内存*/
#include <stdio.h>
#include <stdlib.h>		//包含malloc()函数原型 

struct Student			//结构体
{
    int sid;
    int age;
};
struct Student *CreatStudent(void);			//函数原型 跨函数使用分配内存 返回struct Student * 类型    形参为 空
void ShowStudent(struct Student *);				//函数原型 打印数据 返回void 类型  形参为struct Student *类型
int main(void)
{
    struct Student * ps;
    ps = CreatStudent();
    ShowStudent(ps);
    
    return 0;
}
void ShowStudent(struct Student * pst)
{
    printf("%d  %d",pst->sid,pst->age);
}

struct Student *CreatStudent(void)
{
    struct Student * p = (struct Student*)malloc(sizeof(struct Student));
    p->sid = 99;
    p->age = 88;
    return p;
}
程序运行示例:
-----------------------------
99  88
-----------------------------