Standard C++ Library
Copyright 1998, Rogue Wave Software, Inc.

NAME

 
cin
 
 - Controls input from a stream buffer associated with the object stdin declared in <cstdio>.
 
 
 

SYNOPSIS

 
 
#include <iostream>
extern istream cin;
istream cin;
 
 
 

DESCRIPTION

 
 
The object cin controls input from a stream buffer associated with the object stdin declared in <cstdio>. By default, the standard C and C++ streams are synchronized, but you can improve performance by using the ios_base member function synch_with_stdio to desynchronize them. 
 
After the object cin is initialized, cin.tie() returns &cout, which implies that cin and cout are synchronized. 
 
 
 

EXAMPLE

 
 
 
//
// cin example #1
//
#include <iostream>
 
void main ( )
{

using namespace std;

int i;
float f;
char c;

//read an integer, a float and a character from stdin

cin >> i >> f >> c;

// output i, f and c to stdout

cout << i << endl << f << endl << c << endl;

}
 
//
// cin example #2
//
#include <iostream>
 
void main ( )
{

using namespace std;

char p[50];

// remove all the white spaces

cin >> ws;

// read characters from stdin until a newline
// or 49 characters have been read

cin.getline(p,50);

// output the result to stdout

cout << p;

}
 
When inputting "  Grendel the monster" (newline) in the previous test, the output is "Grendel the monster". The manipulator ws removes spaces. 
 
 
 

SEE ALSO

 
 
basic_istream(3C++), basic_iostream(3C++), basic_filebuf(3C++), cout(3C++), cerr(3C++), clog(3C++), wcin(3C++), wcout(3C++), wcerr(3C++), wclog(3C++), ios_base(3C++), basic_ios(3C++)
 
Working Paper for Draft Proposed International Standard for Information Systems--Programming Language C++, Section 27.3.1
 
 
 

STANDARDS CONFORMANCE

 
 
ANSI X3J16/ISO WG21 Joint C++ Committee
 

Rogue Wave Software  —  Last change: 02 Apr 1998