Standard library header <iosfwd>

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This header contains forward declarations for the Input/output library.

Forward declarations

Defined in header <string>
std::char_traits Class Template which describes properties of a character type (class template)
std::char_traits<char> (class template specialization)
std::char_traits<wchar_t> (class template specialization)
std::char_traits<char16_t> (C++11) (class template specialization)
std::char_traits<char32_t> (C++11) (class template specialization)
Defined in header <memory>
the default allocator
(class template)
Defined in header <ios>
manages an arbitrary stream buffer
(class template)
represents absolute position in a stream or a file
(class template)
Defined in header <streambuf>
abstracts a raw device
(class template)
Defined in header <ostream>
wraps a given abstract device (std::basic_streambuf)
and provides high-level output interface
(class template)
Defined in header <istream>
wraps a given abstract device (std::basic_streambuf)
and provides high-level input interface
(class template)
wraps a given abstract device (std::basic_streambuf)
and provides high-level input/output interface
(class template)
Defined in header <fstream>
implements raw file device
(class template)
implements high-level file stream input operations
(class template)
implements high-level file stream output operations
(class template)
implements high-level file stream input/output operations
(class template)
Defined in header <sstream>
implements raw string device
(class template)
implements high-level string stream input operations
(class template)
implements high-level string stream output operations
(class template)
implements high-level string stream input/output operations
(class template)
Defined in header <syncstream>
synchronized output device wrapper
(class template)
synchronized output stream wrapper
(class template)
Defined in header <strstream>
(deprecated)
implements raw character array device
(class)
(deprecated)
implements character array input operations
(class)
(deprecated)
implements character array output operations
(class)
(deprecated)
implements character array input/output operations
(class)

Typedefs and specializations

std::streampos fpos<char_traits<char>::state_type>
std::wstreampos fpos<char_traits<wchar_t>::state_type>
In addition, for each class template std::basic_T declared in this header, std::T and std::wT are declared as a synonym of std::basic_T<char> and std::basic_T<wchar_t> respectively.

Synopsis

namespace std {

    template<class charT> class char_traits;
    template<> class char_traits<char>;
    template<> class char_traits<char16_t>;
    template<> class char_traits<char32_t>;
    template<> class char_traits<wchar_t>;

    template<class T> class allocator;

    template <class charT, class traits = char_traits<charT> >
        class basic_ios;

    template <class charT, class traits = char_traits<charT> >
        class basic_streambuf;
    template <class charT, class traits = char_traits<charT> >
        class basic_istream;
    template <class charT, class traits = char_traits<charT> >
        class basic_ostream;
    template <class charT, class traits = char_traits<charT> >
        class basic_iostream;
    template <class charT, class traits = char_traits<charT>,
            class Allocator = allocator<charT> >
        class basic_stringbuf;

    template <class charT, class traits = char_traits<charT>,
            class Allocator = allocator<charT> >
        class basic_istringstream;
    template <class charT, class traits = char_traits<charT>,
            class Allocator = allocator<charT> >
        class basic_ostringstream;
    template <class charT, class traits = char_traits<charT>,
            class Allocator = allocator<charT> >
        class basic_stringstream;

    template <class charT, class traits = char_traits<charT> >
        class basic_filebuf;
    template <class charT, class traits = char_traits<charT> >
        class basic_ifstream;
    template <class charT, class traits = char_traits<charT> >
        class basic_ofstream;
    template <class charT, class traits = char_traits<charT> >
        class basic_fstream;

    template <class charT, class traits = char_traits<charT>,
            class Allocator = allocator<charT> >
        class basic_syncbuf;
    template <class charT, class traits = char_traits<charT>,
            class Allocator = allocator<charT> >
        class basic_osyncstream;

    template <class charT, class traits = char_traits<charT> >
        class istreambuf_iterator;
    template <class charT, class traits = char_traits<charT> >
        class ostreambuf_iterator;


    typedef basic_ios<char>     ios;    
    typedef basic_ios<wchar_t>  wios;   

    typedef basic_streambuf<char>     streambuf;
    typedef basic_istream<char>       istream;
    typedef basic_ostream<char>       ostream;
    typedef basic_iostream<char>      iostream;

    typedef basic_stringbuf<char>     stringbuf;
    typedef basic_istringstream<char> istringstream;
    typedef basic_ostringstream<char> ostringstream;
    typedef basic_stringstream<char>  stringstream;

    typedef basic_filebuf<char>       filebuf;
    typedef basic_ifstream<char>      ifstream;
    typedef basic_ofstream<char>      ofstream;
    typedef basic_fstream<char>       fstream;

    typedef basic_syncbuf<char>       syncbuf;
    typedef basic_osyncstream<char>   osyncstream;

    typedef basic_streambuf<wchar_t>     wstreambuf;
    typedef basic_istream<wchar_t>       wistream;
    typedef basic_ostream<wchar_t>       wostream;
    typedef basic_iostream<wchar_t>      wiostream;

    typedef basic_stringbuf<wchar_t>     wstringbuf;
    typedef basic_istringstream<wchar_t> wistringstream;
    typedef basic_ostringstream<wchar_t> wostringstream;
    typedef basic_stringstream<wchar_t>  wstringstream;

    typedef basic_filebuf<wchar_t>       wfilebuf;        
    typedef basic_ifstream<wchar_t>      wifstream;      
    typedef basic_ofstream<wchar_t>      wofstream;      
    typedef basic_fstream<wchar_t>       wfstream;

    typedef basic_syncbuf<wchar_t>       wsyncbuf;
    typedef basic_osyncstream<wchar_t>   wosyncstream;

    template <class state> class fpos;      
    typedef fpos<char_traits<char>::state_type> streampos;  
    typedef fpos<char_traits<wchar_t>::state_type> wstreampos;  

}