30. Write a program that prompts the user the name of a file and then counts and displays the number of bytes in the file. And create a duplicate file with the word ’.backup’ appended to the file name. Please check whether file was successfully opened, and display an error message, if not.

#include<stdio.h>

#include<conio.h>

#include<process.h>

#include<string.h>

void main()

{

          int IntFileSize=0,i;

          char chUserFile[20],c;

          FILE*F1User,*F1Bak;

          clrscr();

          printf("\n Please insert Filename & Extansion -> ");

          scanf("%s", chUserFile);

          F1User=fopen(chUserFile,"r");

          if(F1User==NULL)

          {

                   printf("File does not exist or File I/O Error");

                   getch();

                   exit(0);

          }

          strcat(chUserFile,".backup");

          F1Bak=fopen(chUserFile,"w");

          if(F1User==NULL)

          {

                   printf("File I/O Error!");

                   getch();

                   exit(0);

          }

          while((c=getc(F1User))!=EOF)

          {

                   putc(c,F1Bak);

                   IntFileSize++;

          }

          printf("\n file is %d bytes", IntFileSize);

          fclose(F1User);

          fclose(F1Bak);

          getch();

}