void book_add()
{
    int i=0;
    FILE* fp;
    char in;
    for(;;)
    {
        i++;
        if(head==NULL)
        {
            head=p1=p2=(struct Book*)malloc(sizeof(struct Book));
            head->next=NULL;
        }
        else
        {
            p1=(struct Book*)malloc(sizeof(struct Book));
            p1->next=NULL;
        }
        printf("编号:\n");
        gets(p1->num);
        printf("书名:\n");
        gets(p1->name);
        printf("作者:\n");
        gets(p1->writer);
        printf("分类号:\n");
        gets(p1->fenlei);
        printf("出版单位:\n");
        gets(p1->pubdanwei);
        printf("出版时间:\n");
        gets(p1->pubtime);
        printf("价格:\n");
        p1->price=0.0f;
        scanf("%f",&(p1->price));
        getchar();
        p2->next=p1;
        p2=p1;
        if((fp=fopen("Book.txt","rb"))==NULL)
        {
            fp=fopen("Book.txt","wb");
        }
        fwrite((char*)p1,sizeof(struct Book),1,fp);
        fclose(fp);
        printf("信息录入完毕,随意键退出\n");
        break;
    }
}
void book_view()
{
    int i=0;
    BOOK *p=NULL;
    p=head;
    for(;p!=NULL;)
    {
        i++;
        printf("-------共有%d条记录--------\n",i);
        printf("编号:%s\n",p1->num);
        printf("书名:%s\n",p1->name);
        printf("作者:%s\n",p1->writer);
        printf("分类号:%s\n",p1->fenlei);
        printf("出版单位:%s\n",p1->pubdanwei);
        printf("出版时间:%s\n",p1->pubtime);
        printf("价格:%f\n",p1->price);
        p=p->next;
    }
}   其中的p,p1已经在外部定义为了全局变量，查询和录入的菜单没有问题