I have tried to intend it.

Thank you very much for taking time. I am from India and here we learn about only basics of c++ and our syllabus is based on turbo c++ 3. So i use turbo c++ and i don't know much about c++ programing. So i cannot implement instructions you give on modern c++.

I tried new changes. But i still have some little problems. The program is to transfer content of one file to another. When i input only one entry, the program works. But when more than one entry is used it out puts only 1 or 2. Kindly please correct the problem.

Here is the new code by correcting the previous errors.


Code:
 
#include<fstream.h>
#include<iostream.h>
#include<conio.h>
class student
{
       int rollno;
       char name[20];
       int tm;
       public:
       void input();
       void transfer();
       void output();
 };
void student::input()
{
       char ch='y';
       ofstream outf;
       outf.open("mark.dat");
       while(ch=='y')
      {
               cout<<"Enter rollno, name and mark\n";
               cin>>rollno>>name>>tm;
               outf.write((char*)this,sizeof(student));
               cout<<"Wish to enter more(Y/N)?\n";
               cin>>ch;
      }
     outf.close();
}
void student::transfer()
{
    ofstream outf;
    ifstream inf;
    inf.open("mark.dat");
    outf.open("trans.dat");
    while( inf.read(( char* )this,sizeof(student))) 
   {
          outf.write(( char* )this,sizeof( student ) );
   }
   outf.close();
   inf.close();
}
void student::output()
{
   ifstream inf;
   inf.open("trans.dat");
   while (inf.read((char*)this, sizeof(student)))
   {
        inf.read(( char* )this,sizeof( student ) );
        cout<<"\nRollno "<<rollno;
        cout<<"\tName "<<name;
        cout<<"\tTotal "<<tm<<'\n';
   }
   inf.close();
}
void main()
{
    clrscr();
    student obj;
    obj.input();
    obj.transfer();
    obj.output();
    getch();
 }