C++ Library -

Description

It is used to input-Output forward declarations,this header provides forward declarations for the types of the standard input/output library.

Defines

Following is the defines for iosfwd function.

 #define _GLIBCXX_IOSFWD

Example

C++98

In below example explains about iosfwd function.

amespace std {
   template struct char_traits;
   template<> class char_traits;
   template<> class char_traits;

   template class allocator;

   template  > class basic_ios;
   template  > class basic_streambuf;
   template  > class basic_istream;
   template  > class basic_ostream;
   template  > class basic_iostream;
 
   template , class Alloc=allocator >
      class basic_stringbuf;
   template , class Alloc=allocator > 
      class basic_istringstream;
   template , class Alloc=allocator >
      class basic_ostringstream;
   template , class Alloc=allocator >
      class basic_stringstream;

   template  > class basic_filebuf;
   template  > class basic_ifstream;
   template  > class basic_ofstream;
   template  > class basic_fstream;

   template  > class istreambuf_iterator;
   template  > class ostreambuf_iterator;

   template class fpos;

   typedef basic_ios              ios;
   typedef basic_streambuf        streambuf;
   typedef basic_istream          istream;
   typedef basic_ostream          ostream;
   typedef basic_iostream         iostream;
   typedef basic_stringbuf        stringbuf;
   typedef basic_istringstream    istringstream;
   typedef basic_ostringstream    ostringstream;
   typedef basic_stringstream     stringstream;
   typedef basic_filebuf          filebuf;
   typedef basic_ifstream         ifstream;
   typedef basic_ofstream         ofstream;
   typedef basic_fstream          fstream;

   typedef basic_ios           wios;
   typedef basic_streambuf     wstreambuf;
   typedef basic_istream       wistream;
   typedef basic_ostream       wostream;
   typedef basic_iostream      wiostream;
   typedef basic_stringbuf     wstringbuf;
   typedef basic_istringstream wistringstream;
   typedef basic_ostringstream wostringstream;
   typedef basic_stringstream  wstringstream;
   typedef basic_filebuf       wfilebuf;
   typedef basic_ifstream      wifstream;
   typedef basic_ofstream      wofstream;
   typedef basic_fstream       wfstream;

   typedef fpos streampos;
   typedef fpos wstreampos;
}

C++11

In below example explains about iosfwd function.

namespace std {
   template struct char_traits;
   template<> class char_traits;
   template<> class char_traits;
   template<> class char_traits;
   template<> class char_traits;

   template class allocator;

   template  > class basic_ios;
   template  > class basic_streambuf;
   template  > class basic_istream;
   template  > class basic_ostream;
   template  > class basic_iostream;
 
   template , class Alloc=allocator >
      class basic_stringbuf;
   template , class Alloc=allocator > 
      class basic_istringstream;
   template , class Alloc=allocator >
      class basic_ostringstream;
   template , class Alloc=allocator >
      class basic_stringstream;

   template  > class basic_filebuf;
   template  > class basic_ifstream;
   template  > class basic_ofstream;
   template  > class basic_fstream;

   template  > class istreambuf_iterator;
   template  > class ostreambuf_iterator;

  template class fpos;

   typedef basic_ios              ios;
   typedef basic_streambuf        streambuf;
   typedef basic_istream          istream;
   typedef basic_ostream          ostream;
   typedef basic_iostream         iostream;
   typedef basic_stringbuf        stringbuf;
   typedef basic_istringstream    istringstream;
   typedef basic_ostringstream    ostringstream;
   typedef basic_stringstream     stringstream;
   typedef basic_filebuf          filebuf;
   typedef basic_ifstream         ifstream;
   typedef basic_ofstream         ofstream;
   typedef basic_fstream          fstream;

   typedef basic_ios           wios;
   typedef basic_streambuf     wstreambuf;
   typedef basic_istream       wistream;
   typedef basic_ostream       wostream;
   typedef basic_iostream      wiostream;
   typedef basic_stringbuf     wstringbuf;
   typedef basic_istringstream wistringstream;
   typedef basic_ostringstream wostringstream;
   typedef basic_stringstream  wstringstream;
   typedef basic_filebuf       wfilebuf;
   typedef basic_ifstream      wifstream;
   typedef basic_ofstream      wofstream;
   typedef basic_fstream       wfstream;

   typedef fpos streampos;
   typedef fpos wstreampos;
}