C program that copies contents of a text file into another file

Write a program that copies contents of a text file into another file. Use command line arguments to enter source and destination file name. If source file does not exist print appropriate message and terminate the program.

#include <stdio.h> 
#include <stdlib.h>   
int main() 
{ 
    FILE *fptr1, *fptr2; 
    char filename[100], c; 
  
    printf("Enter the filename to open for reading \n"); 
    scanf("%s", filename); 
  
    // Open one file for reading 
    fptr1 = fopen(filename, "r"); 
    if (fptr1 == NULL) 
    { 
        printf("Cannot open file %s \n", filename); 
        exit(0); 
    } 
  
    printf("Enter the filename to open for writing \n"); 
    scanf("%s", filename); 
  
    // Open another file for writing 
    fptr2 = fopen(filename, "w"); 
    if (fptr2 == NULL) 
    { 
        printf("Cannot open file %s \n", filename); 
        exit(0); 
    } 
  
    // Read contents from file 
    c = fgetc(fptr1); 
    while (c != EOF) 
    { 
        fputc(c, fptr2); 
        c = fgetc(fptr1); 
    } 
  
    printf("\nContents copied to %s", filename); 
  
    fclose(fptr1); 
    fclose(fptr2); 
    return 0; 
}