C File Handling: FILE* Handles, fopen(), fclose() & Text I/O Masterclass

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

int main(void) {
    const char *filename = "students.txt";

    // 1. WRITE DATA TO FILE
    FILE *write_fp = fopen(filename, "w");
    if (write_fp == NULL) {
        perror("Error opening file for writing");
        return EXIT_FAILURE;
    }

    fprintf(write_fp, "Ravi 85.5\n");
    fprintf(write_fp, "Anitha 92.0\n");
    fprintf(write_fp, "Kiran 78.2\n");
    fclose(write_fp); // Flush buffers & close stream!

    printf("Student records successfully written to %s\n\n", filename);

    // 2. READ & PARSE DATA FROM FILE
    FILE *read_fp = fopen(filename, "r");
    if (read_fp == NULL) {
        perror("Error opening file for reading");
        return EXIT_FAILURE;
    }

    char name[50];
    float marks;
    int count = 0;
    float total = 0.0f;

    printf("--- READING STUDENT RECORDS ---\n");
    while (fscanf(read_fp, "%49s %f", name, &marks) == 2) {
        printf("Student %d: %-10s | Marks: %.1f\n", ++count, name, marks);
        total += marks;
    }

    if (count > 0) {
        printf("Average Class Marks: %.2f\n", total / count);
    }

    fclose(read_fp);
    return EXIT_SUCCESS;
}