/*
   testfile2.cpp
   CIS 150
   6/3/2008
   David Klick
   
   This program demonstrates some simple file I/O
   techniques. This is a working version of testfile1.cpp.
*/

#include <iostream>
#include <fstream>
using std::cin;
using std::cout;
using std::ofstream;
using std::ifstream;

void cont();

int main() {
   // create some data to write to file
   int n = 17;
   double x = 37.887;
   bool flag = true;

   // open a file for writing
   cout << "Opening output file\n";
   ofstream outfile("datafile1.txt");
   
   // display error and exit if file didn't open
   if (!outfile) {
      cout << "Error: could not open output file.\n";
      return 1;
   }
   
   // write some data out to file
   //   - The problem with writing and reading has been
   //     fixed by putting a delimiter after each value
   //     as it is written.
   cout << "Writing data to file:\n";
   cout << "n    = " << n << '\n';
   cout << "flag = " << flag << '\n';
   cout << "x    = " << x << '\n';
   outfile << n << '\n';
   outfile << flag << '\n';
   outfile << x << '\n';
   
   // done processing - close file
   outfile.close();
   cout << "File created\n";

   // open the file we created for reading
   cout << "Opening input file\n";
   ifstream infile("datafile1.txt");
   
   // display error and exit if file didn't open
   if (!infile) {
      cout << "Error: could not open input file.\n";
      return 2;
   }
   
   // read some data from the file and display it
   cout << "Reading data from file\n";
   infile >> n >> flag >> x;
   cout << "n    = " << n << '\n';
   cout << "flag = " << flag << '\n';
   cout << "x    = " << x << '\n';
   
   // done processing - close file
   infile.close();
   cout << "Program done\n";
   
   cont();
   return 0;
}

void cont() {
   if (cin.rdbuf()->sungetc() != -1 && cin.get() != '\n') cin.ignore(80,'\n');
   cout << "Press enter to continue...";
   cin.get();
}

/*
   Sample run:
   
   Opening output file
   Writing data to file:
   n    = 17
   flag = 1
   x    = 37.887
   File created
   Opening input file
   Reading data from file
   n    = 17
   flag = 1
   x    = 37.887
   Program done
   Press enter to continue...
*/