Need help eliminating errors from this program

[fanronnie80]

I have written a menu driven program that has file handling in it. It shows particular error with file handing. I have declared an object 'f' of fstream class but the compiler says "fstream does name a type".

/*Aim-To define a class named 'student',accept,display,search by rollno,search by name,modify by usinf file handling*/
#include<fstream>
#include<iostream>
#include<ctype.h>
#include<stdio.h>
#include<stdlib.h>
#include<string.h>
using namespace std;
void readfile();
void writefile();
void modify(int);
void search(int);
void search(char *);

class student
{private:
int rollno;
char name[20];

public:
void getdata();
void putdata();
int retrollno()
{return rollno;}
char *retname()
{return name;}
}s;
fstream f;

void writefile()
{f.open("Stud.dat",ios::binary|ios::app);
cout<<"Enter data\n";
s.getdata();
f.write((char *)&s,sizeof(s));
f.close();}

void student::getdata()
{cout<<"Enter name\n";
cin>>name;
cout<<"Enter roll no\n";
cin>>rollno;}

void readfile()
{f.open("Stud.dat",ios::binary|ios::in);

while(f.read((char *)&s,sizeof(s)))
s.putdata();
f.close();}

void student::putdata()
{cout<<"Roll no - "<<rollno<<"\n";
cout<<"Name - "<<name<<"\n";}

fstream f1;

void modify(int val)
{
f.open("Stud.dat",ios::binary|ios::in);
f1.open("Temp.dat",ios::binary|ios::out);
while(f.read((char *)&s,sizeof(student)))
    {if(s.retrollno()==val)
	{cout<<"Found\n";
	cout<<"Enter new data\n";
	s.getdata();}
	f1.write((char *)&s,sizeof(student));
	}
f.close();
f1.close();
remove("Stud.dat");
rename("Temp.dat","Stud.dat");}

void search(int val)
{int flag=0;
f.open("Stud.dat",ios::binary|ios::in);
while(f.read((char *)&s,sizeof(student)))
{   if(s.retrollno()==val)
	{cout<<"Found\n";
	flag=1;
	s.putdata();
	break;}}
    f.close();
if(flag==0)
cout<<"Not found \n";}

void search(char *n)
{int flag=0;
f.open("Stud.dat",ios::binary|ios::in);
while(f.read((char *)&s,sizeof(student)))
{if(strcmpi(s.retname(),n)==0)
    {
	cout<<"Found\n";
	s.putdata();
	flag=1;
	break;
    }
}
f.close();
if(flag==0)
{
    cout<<"Not found\n";
}
}
int main()
{int choice,n;
char ch,tempname[20];
do
{
cout<<"1)Enter data\n";
cout<<"2)Display data\n";
cout<<"3)Search by roll no\n";
cout<<"4)Search by name\n";
cout<<"5)Modify\n";
cout<<"6)Exit\n";
cout<<"Enter choice\n";
cin>>choice;
switch(choice)
{
    case 1:
    writefile();
    break;

    case 2:
    readfile();
    break;

    case 3:
    cout<<"Enter roll no to search\n";
    cin>>n;
    search(n);
    break;

    case 4:
    cout<<"Enter name to search\n";
    cin>>tempname;
    search(tempname);
    break;

    case 5:
    cout<<"Enter roll no to search\n";
    cin>>n;
    modify(n);
    break;

    case 6:
    exit(0);
    break;
}
cout<<"Do you want to continue?\n";
cin>>ch;
}while((ch=='y')||(ch=='Y'));
return 0;
}

Edit 1: I edited the program and eliminated many errors. But there are still 2 errors:
1)In line 65, "|65|error: no matching function for call to 'std::basic_fstream<char, std::char_traits<char> >::close(const char [9])'| "
2)In line 66, "|66|error: no matching function for call to 'std::basic_fstream<char, std::char_traits<char> >::close(const char [9])'| "

Edit 2: I finally eliminated all the errors in the program. In line 65 and line 66 , there was no need to provide the file names.

Edit 3: I again edited this program and it is working but somehow whatever
I input is not saved in the file "Stud.dat". What should I do?

[vlad from moscow]

You should either use nested name with namespace std as for example

std::fstream f;

or include using deirective

using namespace std;

in your code.