/*Demonstrate how seek and read work*/
#include <iostream>
#include <iomanip>
#include <fstream>
#include <string>
#include <strstream>

using namespace std;

const int WIDTH = 10;
const int SPACE = WIDTH+1;

int main(int argc, char* argv[])
{
	//Get name of file
	string filename;
	if( argc > 1 )
	{
		filename=argv[1];
	} else {
		filename="11peek.cpp";
	}
	cout << "file named " << filename<<endl;
	//open file for input
        ifstream fs (filename.c_str() );

        if(fs){//opened
		cout << "From 0";
		fs . seekg(0,ios::end);
		cout  << " To  " <<fs.tellg()<<endl;
                char word[SPACE];
		word[WIDTH]='\0';

		int cn;//character number
		cout << "Which "<< WIDTH <<" characters next? ";  
		while(cin  >>cn)
		{
			fs . seekg(cn,ios::beg);
			cout  << "From " <<fs.tellg()<<endl;
			fs . read( word, WIDTH );
			cout  << "`" << word << "`"<< endl;
			cout  << "     To " <<fs.tellg()<<endl;
			cout << "Next? ";  
		}// while more

                fs . close();
        }
        else // didn't open file
        {       cerr << "File " << filename <<" not opened!\n";
		return 0;
        }
}