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<istream> operators

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operator>>

Extracts characters and strings from the stream.

template <class Elem, class Tr>
basic_istream<Elem, Tr>& operator>>(
    basic_istream<Elem, Tr>& Istr,
    Elem* str);

template <class Elem, class Tr>
basic_istream<Elem, Tr>& operator>>(
    basic_istream<Elem, Tr>& Istr,
    Elem& Ch);

template <class Tr>
basic_istream<char, Tr>& operator>>(
    basic_istream<char, Tr>& Istr,
    signed char* str);

template <class Tr>
basic_istream<char, Tr>& operator>>(
    basic_istream<char, Tr>& Istr,
    signed char& Ch);

template <class Tr>
basic_istream<char, Tr>& operator>>(
    basic_istream<char, Tr>& Istr,
    unsigned char* str);

template <class Tr>
basic_istream<char, Tr>& operator>>(
    basic_istream<char, Tr>& Istr,
    unsigned char& Ch);

template <class Elem, class Tr, class Type>
basic_istream<Elem, Tr>& operator>>(
    basic_istream<char, Tr>&& Istr,
    Type& val);

Parameters

Ch
A character.

Istr
A stream.

str
A string.

val
A type.

Return Value

The stream

Remarks

The basic_istream class also defines several extraction operators. For more information, see basic_istream::operator>>.

The function template:

template <class Elem, class Tr>
basic_istream<Elem, Tr>& operator>>(
    basic_istream<Elem, Tr>& Istr, Elem* str);

extracts up to N - 1 elements and stores them in the array starting at str. If Istr.width is greater than zero, N is Istr.width; otherwise, it's the size of the largest array of Elem that can be declared. The function always stores the value Elem() after any extracted elements it stores. Extraction stops early on end of file, on a character with value Elem(0) (which isn't extracted), or on any element (which isn't extracted) that would be discarded by ws. If the function extracts no elements, it calls Istr.setstate(failbit). In any case, it calls Istr.width(0) and returns Istr.

Security Note The null-terminated string being extracted from the input stream must not exceed the size of the destination buffer str. For more information, see Avoiding Buffer Overruns.

The function template:

template <class Elem, class Tr>
basic_istream<Elem, Tr>& operator>>(
    basic_istream<Elem, Tr>& Istr, Elem& Ch);

extracts an element, if possible, and stores it in Ch. Otherwise, it calls is.setstate(failbit). In any case, it returns Istr.

The function template:

template <class Tr>
basic_istream<char, Tr>& operator>>(
    basic_istream<char, Tr>& Istr, signed char* str);

returns Istr >> ( char * ) str.

The function template:

template <class Tr>
basic_istream<char, Tr>& operator>>(
    basic_istream<char, Tr>& Istr, signed char& Ch);

returns Istr >> ( char& ) Ch.

The function template:

template <class Tr>
basic_istream<char, Tr>& operator>>(
    basic_istream<char, Tr>& Istr, unsigned char* str);

returns Istr >> ( char * ) str.

The function template:

template <class Tr>
basic_istream<char, Tr>& operator>>(
    basic_istream<char, Tr>& Istr, unsigned char& Ch);

returns Istr >> ( char& ) Ch.

The function template:

template <class Elem, class Tr, class Type>
basic_istream<Elem, Tr>& operator>>(
    basic_istream<char, Tr>&& Istr,
    Type& val);

returns Istr >> val (and converts an rvalue reference to Istr to an lvalue in the process).

Example

// istream_op_extract.cpp
// compile with: /EHsc
#include <iostream>
using namespace std;

int main( )
{
   ws( cin );
   char c[10];

   cin.width( 9 );
   cin >> c;
   cout << c << endl;
}

See also

<istream>