The use of streams with files. This programme copy the input file to another file and also print its contents to the IO Stream.

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*     MYCPLUS Sample Code - https://www.mycplus.com     *
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*   This code is made available as a service to our   *
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#include 
#include 
#include 


void main()
{
ifstream infile;
ofstream outfile;
ofstream printer;
char filename[20];


   cout << "Enter the desired file to copy ----> ";


   cin >> filename;


   infile.open(filename, ios::nocreate);
   if (!infile) {
      cout << "Input file cannot be opened.\n";
      exit(1);
   }


   outfile.open("copy");
   if (!outfile) {
      cout << "Output file cannot be opened.\n";
      exit(1);
   }


   printer.open("PRN");
   if (!printer) {
      cout << "There is a problem with the printer.\n";
      exit(1);
   }


   cout << "All three files have been opened.\n";


char one_char;


   printer << "This is the beginning of the printed copy.\n\n";


   while (infile.get(one_char)) {
      outfile.put(one_char);
      printer.put(one_char);
   }


   printer << "\n\nThis is the end of the printed copy.\n";


   infile.close();
   outfile.close();
   printer.close();


}


// Result of execution
//
// (The input file is copied to the file named "COPY")
// (The input file is printed on the printer