C语言操作文件

#include <stdio.h>
struct stu{
        char name[];
        int num;
        int age;
        char addr[];
}boya[],boyb[];

struct stu *pa,*pb;

main(){
        FILE *fp;
        char ch;
        int i;
        pa=boya;
        pb=boyb;
        //open a file
        fp=fopen("stulist","wb+");
        printf("input data\n");
        for(i=;i<;i++,pa++){
                scanf("%s%d%d%s",pa->name,&pa->num,&pa->age,pa->addr);
        }
        fwrite(boya,sizeof(struct stu),,fp);

        rewind(fp);
        fread(pb,sizeof(struct stu),,fp);
        printf("%10s%10s%10s%10s\n","name","number","age","address");
        for(i=;i<;i++){
                printf("%10s%10d%10d%10s\n",pb->name,pb->num,pb->age,pb->addr);
                pb++;
        }
        fclose(fp);
}

#include <stdio.h>

struct stu{
        char name[];
        int num;
        int age;
        char addr[];
}boy,*p;

int main(){
        FILE *fp;
        char ch;
        int i;

        fp=fopen("stulist","rb");
        printf("name\tnumber\tage\taddr\n");
        p=&boy;
        for(i=;i<;i++){
                fseek(fp,i*sizeof(struct stu),);
                fread(p,sizeof(struct stu),,fp);
                //printf("%s\t%d\t%d\t%s\n",(*p).name,(*p).num,(*p).age,(*p).addr);
                printf("%s\t%d\t%d\t%s\n",p->name,p->num,p->age,p->addr);
                p++;
        }
}