Read/Write Structure to a File

1#include <stdio.h>
2
3struct Student {
4    int id;
5    char name[50];
6    float gpa;
7};
8
9int main() {
10    struct Student students[] = {
11        {101, "Alice", 3.9},
12        {102, "Bob", 3.7},
13        {103, "Charlie", 3.5}
14    };
15    int n = 3;
16    
17    // Write to binary file
18    FILE *fp = fopen("students.dat", "wb");
19    if (fp == NULL) {
20        printf("Error opening file!\n");
21        return 1;
22    }
23    
24    fwrite(students, sizeof(struct Student), n, fp);
25    fclose(fp);
26    printf("Data written to students.dat\n\n");
27    
28    // Read from binary file
29    struct Student readStudents[3];
30    
31    fp = fopen("students.dat", "rb");
32    if (fp == NULL) {
33        printf("Error opening file!\n");
34        return 1;
35    }
36    
37    fread(readStudents, sizeof(struct Student), n, fp);
38    fclose(fp);
39    
40    printf("Data read from file:\n");
41    for (int i = 0; i < n; i++) {
42        printf("ID: %d, Name: %s, GPA: %.2f\n",
43               readStudents[i].id,
44               readStudents[i].name,
45               readStudents[i].gpa);
46    }
47    
48    return 0;
49}