include

struct Person { char name[50]; int age; };

int main() { FILE *file; struct Person person;

file = fopen("person.dat", "wb");

if (file == NULL) {
    printf("Error opening file.");
    return 1;
}

strcpy(person.name, "John");
person.age = 30;

fwrite(&person, sizeof(struct Person), 1, file);

fclose(file);

return 0;

}