下列是一个管理系统的输入和存储部分，请高手帮忙看下我的这个为什么存储错误。我用文档打开存储的文件，里面是乱码，改成以W形式输入也不行。是不是使用的存储函数错误？请教下大家像学生管理系统存储信息的建立和使用一般用什么函数？下面程序可能运行一下更能找出我的错误吧。编写环境是TC2.0(初学，不敢用VC）。谢谢大家看完我的帖子。
#include<stdio.h>
#include<malloc.h>
#include <string.h>
#define NULL 0
#define len sizeof(struct student)
struct student
{long num;
 char name[20];
 float msco;
 float csco;
 float esco;
 struct student *next;
};
 int n;
 struct student *creat()
{
 struct student *head;
 struct student *p1,*p2;
 n=0;
 do
 {
   p1=(struct student *)malloc(len);
   printf("please input the number of the student:");
   scanf("%ld",&p1->num);
   if(p1->num==0)break;
   printf("please input the name of the student:");
   scanf("%s",&p1->name);
   printf("please input the math of the student:");
   scanf("%f",&p1->msco);
   printf("please input the cprogram of the student:");
   scanf("%f",&p1->csco);
   printf("please input the english of the student:");
   scanf("%f",&p1->esco);
   n=n+1;
   if(n==1)head=p1;
   else p2->next=p1;
   p2=p1;
  }while(p1->num!=0);
 p2->next=NULL;
 return(head);
}

void save(struct student *head)
{
 FILE *fp;
 struct student *p;
 fp=fopen("stu_list","wb");
 p=head;
 if(head!=NULL)
  do
   {
    fwrite(p,len,1,fp);
    p=p->next;
   }while(p!=NULL);
fclose(fp);
}
main()
{
 long del_num;
 float arg,*point=&arg;
 struct student *head;
 clrscr();
 head=creat();
 save(head);
}