Binary file-question!!!

Hi!!!I need some help!!!
I have written the following code:

Code:

---

#include <stdio.h>

struct info
{
        float mo;
        int age;
}m;

int main()
{
        int il;
        FILE *fp;
        fp=fopen("sx.txt","rb");
        if (fp==NULL){
                printf("Problem!!!\n");
                exit(0);
        }
        fseek(fp,4,0);
        fread(&m,sizeof(struct info),1,fp);
        printf("Age:%d\n",m.age);
        rewind(fp);
        fread(&m,sizeof(struct info),1,fp);
        printf("Age:%d\n",m.age);
        return 0;
}

---

and put at the file the following numbers:
5 18
8.5 21
10 20
3 18
6 19
The first printf("Age:%d\n",m.age); does not give me the right result(19)..Why???? :confused:

Your file is in plain-text format but you are reading it as if it is a binary-coded format. That's why you get what looks to be junk.

so...what could I change???

Depends upon how it should work :). Either:
1) Change the code to read the file as plain-text, or
2) Change the file so the data is binary-coded.

My file is binary-coded,I had written this code:

Code:

---

#include <stdio.h> 

 

 struct info 

 { 

    float mo; 

    int age; 

}students[5]; 

 

 int main() 

 { 

    FILE *fp; 

    int i; 

    for (i=0; i<5; i++){ 

          scanf("%f%d",&students[i].mo,&students[i].age); 

      } 

      fp=fopen("sx.txt","wb"); 

      fwrite(students,sizeof(struct info),5,fp); 

      fclose(fp); 

      return 0; 
 }

---

:/

Why does it not give the right output???

Code:

---

int main()
{
        int il;
        FILE *fp;
        fp=fopen("sx.txt","rb");
        if (fp==NULL){
                printf("Problem!!!\n");
                exit(0);
        }
        fseek(fp,4,0);
        fread(&m,sizeof(struct info),1,fp);
        printf("Age:%d\n",m.age);
        rewind(fp);
        fread(&m,sizeof(struct info),1,fp);
        printf("Age:%d\n",m.age);
        return 0;
}

---

Look at the '4' in the fseek call. You should be seeking a multiple of sizeof(info).

Edit: And don't give files a 'txt' extension unless they are human-readable. It only confuses things

Nice!!!!Thank you very much!!!!!!! :)