嵌入式学习

笔记

作业

        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

#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <pthread.h>
#include <semaphore.h>
#include <wait.h>
#include <signal.h>
#include <sys/socket.h>
#include <arpa/inet.h>
#include <sys/socket.h>
#include <sys/ipc.h>
#include <sys/sem.h>
#include <semaphore.h>
#include <sys/msg.h>
#include <sys/shm.h>
#include <sys/un.h>#define MAXSIZE 5typedef struct student{char name[16];int age;double math_score;double chinses_score;double english_score;double physics_score;double chemistry_score;double bio_score;
}stu,*stu_p;stu_p create_stu()
{stu_p S=(stu_p)malloc(sizeof(stu));if(NULL==S){printf("空间申请失败\n");return NULL;}return S;
}void Init_stu(stu_p *S,int age,double math_score,double chinses_score,double english_score,double physics_score,double chemistry_score,double bio_score)
{if(NULL==*S){printf("学生信息表不存在\n");return;}//(*S)->name=name;(*S)->age=age;(*S)->math_score=math_score;(*S)->chinses_score=chinses_score;(*S)->english_score=english_score;(*S)->physics_score=physics_score;(*S)->chemistry_score=chemistry_score;(*S)->bio_score=bio_score;
}void print_stu(stu_p *S)
{int i;for(i=0;i<MAXSIZE;i++){printf("%-16s ",S[i]->name);printf("%-d ",S[i]->age);printf("%-6.2lf ",S[i]->math_score);printf("%-6.2lf ",S[i]->chinses_score);printf("%-6.2lf ",S[i]->english_score);printf("%-6.2lf ",S[i]->physics_score);printf("%-6.2lf ",S[i]->chemistry_score);printf("%-6.2lf ",S[i]->bio_score);printf("\n");}
}int main(int argc, const char *argv[])
{stu_p S[MAXSIZE];int i;for(i=0;i<MAXSIZE;i++){S[i]=create_stu();}//这里直接把五名学生信息存入到数组1中strcpy(S[0]->name,"zhangsan");strcpy(S[1]->name,"lisi");strcpy(S[2]->name,"wangwu");strcpy(S[3]->name,"liuliu");strcpy(S[4]->name,"luqi");Init_stu(S,20,100,90,80,100,70,88);Init_stu(S+1,21,99,92,89,98,79,80);Init_stu(S+2,22,87,97,87,90,77,86);Init_stu(S+3,18,89,80,80,99,75,88);Init_stu(S+4,29,98,87,85,89,76,89);//printf("数组S\n");//print_stu(S);FILE *fp;fp=fopen(argv[1],"r");if(NULL==fp){//第一次执行，由于文件不存在，创建文件并把学生信息存入该文件perror("第一次fopen");fp=fopen(argv[1],"w");for(i=0;i<MAXSIZE;i++){fprintf(fp,"%-16s %-3d %-6.2lf %-6.2lf %-6.2lf %-6.2lf %-6.2lf %-6.2lf \n",S[i]->name,S[i]->age,S[i]->math_score,S[i]->chinses_score,S[i]->english_score,S[i]->physics_score,S[i]->chemistry_score,S[i]->bio_score);}fclose(fp);}else {//第二次执行，将学生信息存入第二个数组中FILE *fp2=fopen(argv[1],"r");if(NULL==fp2){perror("第二次fopen");return -1;}stu_p S2[MAXSIZE];for(i=0;i<MAXSIZE;i++){S2[i]=create_stu();fscanf(fp2,"%s %d %lf %lf %lf %lf %lf %lf",S2[i]->name,&(S2[i]->age),&(S2[i]->math_score),&(S2[i]->chinses_score),&(S2[i]->english_score),&(S2[i]->physics_score),&(S2[i]->chemistry_score),&(S2[i]->bio_score));}fclose(fp2);printf("数组S2\n");print_stu(S2);}return 0;
}