1. Sequential input and output Operations in file
for(int i=0; i<len ; i++) {
file.put(string[i]); }
file,seek(0); // goto start
char ch;
while(file)
file.get(ch);
cout << ch;
put()  function is used to write a single character to the associated stream .
get()  function is used to read a single character from the associated stream.
#include<iostream.h>
#include<fstream.h>
#include<string.h>
void main() {
char string[80];
cout << “Enter a string:”;
cin >> string;
int len=strlen(string);
fstream file;
file.open(“Data”.text”, ios::in | ios :: out); // opening the file for input and output

2. Reading and writing a class object
One of the major shorting coming of I/O system of c is that it can not handle the user define data types such as class objects .
But class objects are the central elements of the C++ programming .
The read() and write() binary functions are designed to do so
These function can handle the entire structure of the object as a single unit.