Standard library header <iosfwd>
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<iosfwd>
<print> (C++23)
<spanstream> (C++23)
<strstream> (C++98/26*)
<syncstream> (C++20)
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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)
Defined in header
<memory>
Defined in header
<ios>
Defined in header
<streambuf>
Defined in header
<ostream>
wraps a given abstract device (std::basic_streambuf )
and provides high-level output interface
(class template) [edit]
and provides high-level output interface
(class template) [edit]
Defined in header
<istream>
wraps a given abstract device (std::basic_streambuf )
and provides high-level input interface
(class template) [edit]
and provides high-level input interface
(class template) [edit]
wraps a given abstract device (std::basic_streambuf )
and provides high-level input/output interface
(class template) [edit]
and provides high-level input/output interface
(class template) [edit]
Defined in header
<fstream>
Defined in header
<sstream>
Defined in header
<syncstream>
Defined in header
<spanstream>
Defined in header
<strstream>
(deprecated in C++98)(removed in C++26)
(class) [edit]
Typedefs and specializations
std::streampos
std::fpos <std::char_traits <char>::state_type>
std::wstreampos
std::fpos <std::char_traits <wchar_t>::state_type>
std::u8streampos
std::fpos <std::char_traits <char8_t>::state_type>
std::u16streampos
std::fpos <std::char_traits <char16_t>::state_type>
std::u32streampos
std::fpos <std::char_traits <char32_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.
[edit] Synopsis
namespace std { template<class CharT> struct char_traits; template<> struct char_traits<char>; template<> struct char_traits<char8_t>; template<> struct char_traits<char16_t>; template<> struct char_traits<char32_t>; template<> struct 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 basic_spanbuf; template<class CharT, class Traits = char_traits<CharT>> class basic_ispanstream; template<class CharT, class Traits = char_traits<CharT>> class basic_ospanstream; template<class CharT, class Traits = char_traits<CharT>> class basic_spanstream; template<class CharT, class Traits = char_traits<CharT>> class istreambuf_iterator; template<class CharT, class Traits = char_traits<CharT>> class ostreambuf_iterator; using ios = basic_ios<char>; using wios = basic_ios<wchar_t>; using streambuf = basic_streambuf<char>; using istream = basic_istream<char>; using ostream = basic_ostream<char>; using iostream = basic_iostream<char>; using stringbuf = basic_stringbuf<char>; using istringstream = basic_istringstream<char>; using ostringstream = basic_ostringstream<char>; using stringstream = basic_stringstream<char>; using filebuf = basic_filebuf<char>; using ifstream = basic_ifstream<char>; using ofstream = basic_ofstream<char>; using fstream = basic_fstream<char>; using syncbuf = basic_syncbuf<char>; using osyncstream = basic_osyncstream<char>; using spanbuf = basic_spanbuf<char>; using ispanstream = basic_ispanstream<char>; using ospanstream = basic_ospanstream<char>; using spanstream = basic_spanstream<char>; using wstreambuf = basic_streambuf<wchar_t>; using wistream = basic_istream<wchar_t>; using wostream = basic_ostream<wchar_t>; using wiostream = basic_iostream<wchar_t>; using wstringbuf = basic_stringbuf<wchar_t>; using wistringstream = basic_istringstream<wchar_t>; using wostringstream = basic_ostringstream<wchar_t>; using wstringstream = basic_stringstream<wchar_t>; using wfilebuf = basic_filebuf<wchar_t>; using wifstream = basic_ifstream<wchar_t>; using wofstream = basic_ofstream<wchar_t>; using wfstream = basic_fstream<wchar_t>; using wsyncbuf = basic_syncbuf<wchar_t>; using wosyncstream = basic_osyncstream<wchar_t>; using wspanbuf = basic_spanbuf<wchar_t>; using wispanstream = basic_ispanstream<wchar_t>; using wospanstream = basic_ospanstream<wchar_t>; using wspanstream = basic_spanstream<wchar_t>; template<class State> class fpos; using streampos = fpos<char_traits<char>::state_type>; using wstreampos = fpos<char_traits<wchar_t>::state_type>; using u8streampos = fpos<char_traits<char8_t>::state_type>; using u16streampos = fpos<char_traits<char16_t>::state_type>; using u32streampos = fpos<char_traits<char32_t>::state_type>; } // deprecated namespace std { class strstreambuf; class istrstream; class ostrstream; class strstream; }