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有如下结构体 struct Student{ char name[16]; int age; double math_score; double chinese_score; double english_score; double physics_score; double chemistry_score; double bio_score; }; 申请该结构体数组，容量为5，初始化5个学生的信息 使用fprintf将数组中的5个学生信息，保存到文件中去 下一次程序运行的时候，使用fscanf，将文件中的5个学生信息，写入(加载)到数组中去，并直接输出学生信息

  1 #include <stdio.h>
  2 #include <string.h>
  3 #include <stdlib.h>
  4 #include <sys/types.h>
  5 #include <unistd.h>
  6 #include <sys/stat.h>
  7 #include <fcntl.h>
  8 #include <pthread.h>
  9 #include <semaphore.h>
 10 #include <wait.h>
 11 #include <signal.h>
 12 #include <sys/socket.h>
 13 #include <arpa/inet.h>
 14 #include <sys/socket.h>
 15 #include <sys/ipc.h>
 16 #include <sys/sem.h>
 17 #include <semaphore.h>
 18 #include <sys/msg.h>
 19 #include <sys/shm.h>
 20 #include <sys/un.h>
 21 typedef struct student
 22 {
 23     char name[16];
 24     int age;
 25     double math_score;
 26     double chinese_score;
 27     double english_score;
 28     double physics_score;
 29     double chemistry_score;
 30     double bio_score;
 31 }information;
 32 int main(int argc, const char *argv[])
 33 {
 34     //向堆区空间申请容量为5的内存空间
 35     information *students=(information*)malloc(5*sizeof(information));
 36     if(!students)
 37     {
 38         perror("students:");
 39         return -1;
 40     }
 41     //循环写入学生信息
 42     for(int i=0;i<5;i++)
 43     {
 44         printf("输入学生姓名：");
 45         scanf(" %15s",students[i].name);
 46         printf("输入学生年龄：");
 47         scanf(" %d",&students[i].age);
 48         printf("输入学生数学成绩：");
 49         scanf(" %lf",&students[i].math_score);
 50         printf("输入学生语文成绩：");
 51         scanf(" %lf",&students[i].chinese_score);
 52         printf("输入学生英语成绩：");
 53         scanf(" %lf",&students[i].english_score);
 54         printf("输入学生化学成绩：");
 55         scanf(" %lf",&students[i].chemistry_score);
 56         printf("输入学生生物成绩：");                                                                                                                                                                                                                                                                                                                                                                                  
 57         scanf(" %lf",&students[i].bio_score);
 58     }
 59     //打开文件
 60     FILE *wfp=fopen(argv[1],"w");
 61     if(!wfp)
 62     {
 63         perror("wfp:");
 64         return -1;
 65     }
 66     //将信息录入文件中
 67     for(int i=0;i<5;i++)
 68     {
 69         fprintf(wfp,"姓名:%s\n年龄:%d\n数学成绩:%.1f\n语文成绩:%.1f\n英语成绩:%.1f\n化学成绩:%.1f\n生物成绩:%.1f\n",\
 70             students[i].name,students[i].age,students[i].math_score,students[i].chinese_score,students[i].english_score,\
 71             students[i].chemistry_score,students[i].bio_score);
 72     }
 73     //关闭文件
 74     fclose(wfp);
 75     //打开文件
 76     FILE *rfp=fopen(argv[2],"r");
 77     if(!rfp)
 78     {
 79         perror("rfp:");
 80         return -1;
 81     }
 82     //循环将文件内容赋值给结构体数组
 83     for(int i=0;i<5;i++)
 84     {
 85         if(fscanf(rfp,"姓名:%15s\n年龄:%d\n数学成绩:%lf\n语文成绩:%lf\n英语成绩:%lf\n化学成绩:%lf\n生物成绩:%lf\n",students[i].name,&students[i].age,&students[i].math_score,\
 86                 &students[i].chinese_score,&students[i].english_score,&students[i].chemistry_score,&students[i].bio_score)!=7)
 87         {
 88             perror("rfp:");
 89             free(students);
 90             return -1;
 91         }
 92     }
 93     //循环输出数组元素
 94     for(int i=0;i<5;i++)
 95     {
 96         printf("姓名:%s\n年龄:%d\n数学成绩:%.1f\n语文成绩:%.1f\n英语成绩:%.1f\n化学成绩:%.1f\n生物成绩:%.1f\n",\
 97             students[i].name,students[i].age,students[i].math_score,students[i].chinese_score,students[i].english_score,\
 98              students[i].chemistry_score,students[i].bio_score);
 99     }
100     //关闭文件
101     fclose(rfp);
102     //释放内存
103     free(students);
104     students=NULL;
105     return 0;
106 }
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