Добрый день,
мне надо записать оъекты разных типов в файл:
template<class T>
class ReadWriteToFile
{
private:
T *obj;
public:
ReadWriteToFile(T *);
ReadWriteToFile(T &x);
~ReadWriteToFile(){delete [] obj;}
void writetofile(fstream& );
void readfromfile(fstream&);
void writetoend(fstream&);
void show();

};

template<class T>
ReadWriteToFile<T>::ReadWriteToFile(T *ob)
{
obj=new T;//(ob);
obj=ob;
}
//**************************************
template<class T>
ReadWriteToFile<T>::ReadWriteToFile(T &x)
{
obj=new T(x.ob);
}
//**************************************

template<class T>
void ReadWriteToFile<T>::writetofile(fstream &ot)
{
ot.write(reinterpret_cast<T*>(&obj),sizeof(obj));
}

//*********************************
int main ()
{
char namefile[10];
cout<<"Enter the file name of you file you want to enter the student objs:";
cin>>namefile;
ofstream ot;
ifstream in;
ot.open(namefile,ios::out|ios::binary|ios::ate); //for write and add
assert(ot);
in.open(namefile,ios::out|ios::binary); //for reading
assert(in);
student s1("misha",1,23424);
rrs1.writetofile(ot);

при попытке вызова ф-и rrs1.writetofile(ot);
все время получаю ошибку:

my_program\tar13\tar13.cpp(87) : error C2664: 'writetofile' : cannot convert parameter 1 from 'class std::basic_ofstream<char,struct std::char_traits<char> >' to 'class std::basic_fstream<char,struct std::char_traits<char> > &'
A reference that is not to 'const' cannot be bound to a non-lvalue
Error executing cl.exe.


помогите пожалуйста решить проблему!