/* writeout.cpp

	Written July 2009 by John Bell to illustrate output options
*/

#include <iostream>
#include <fstream>
#include <string>

using namespace std;

void writeout( ostream &out, int data );

int main( void ) {

	bool done;
	char choice;
	int n;
	string filename;
	ofstream fout;

	cout << "\nThis program demonstrates output to various ostreams\n";
	cout << "Written July 2009 by John Bell for CS 109\n";
	while( true ) {

		cerr << "\nEnter an integer, zero to quit: ";
		cin >> n;

		if( !n ) {
			cerr << "\nZero read.  Exiting.\n\n";
			return 0;
		}
	
		done = false;
		while( !done ) {

			cerr << "\nWhere would you like your output written? \n\n";
			cerr << "\tO - Standard output ( cout )\n";
			cerr << "\tE - Standard error ( cerr )\n";
			cerr << "\tF - A file ( to be named. )\n";
			cerr << "\tQ - Quit the program.\n";
			cerr << "\nPlease enter your choice: ";

			cin >> choice;

			switch( choice ) {

				case 'o':
				case 'O':
					cout << "\nWriting to cout:\n";
					writeout( cout, n );
					done = true;
					break;

				case 'e':
				case 'E':
					cerr << "\nWriting to cerr:\n";
					writeout( cerr, n );
					done = true;
					break;

				case 'f':
				case 'F':
					cerr << "\n\tEnter a file name: ";
					cin >> filename;
					fout.open( filename.c_str( ) );
					if( !fout ) {
						cerr << "Error opening " << filename << ".  Please try again.\n";
						fout.clear( );
						break;
					}
					fout << "\nWriting to a file:\n";
					writeout( fout, n );
					fout.close( );
					done = true;
					break;

				case 'q':
				case 'Q':
					cerr << "\nThanks for playing.\n\n";
					exit( 0 );

				default:
					cerr << "\nInvalid choice.  Try again.\n";
					break;

			} // switch

		} // while not done

		cerr << "\nOutput written.  Continuing.\n";

	} // while true ( while not read a zero yet )

	// The following code cannot actually ever be reached.
	cerr << "Zero read.  Exiting.\n\n";
	return 0;

} // main

void writeout( ostream &out, int data ) {

	out << "Function writout outputing " << data << endl;
	return;
}