iostream
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// Standard iostream objects -*- C++ -*-
// Copyright (C) 1997-2025 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library. This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 3, or (at your option)
// any later version.
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file include/iostream
* This is a Standard C++ Library header.
*/
//
// ISO C++ 14882: 27.3 Standard iostream objects
//
#ifndef _GLIBCXX_IOSTREAM
#define _GLIBCXX_IOSTREAM 1
#ifdef _GLIBCXX_SYSHDR
#pragma GCC system_header
#endif
#include <bits/requires_hosted.h> // iostreams
#include <bits/c++config.h>
#include <ostream>
#include <istream>
namespace std _GLIBCXX_VISIBILITY(default)
{
_GLIBCXX_BEGIN_NAMESPACE_VERSION
/**
* @name Standard Stream Objects
*
* The `<iostream>` header declares the eight *standard stream objects*.
* For other declarations, see
* https://gcc.gnu.org/onlinedocs/libstdc++/manual/io.html
* and the @link iosfwd I/O forward declarations @endlink
*
* They are required by default to cooperate with the global C
* library's `FILE` streams, and to be available during program
* startup and termination. For more information, see the section of the
* manual linked to above.
*/
///@{
extern istream cin; ///< Linked to standard input
extern ostream cout; ///< Linked to standard output
extern ostream cerr; ///< Linked to standard error (unbuffered)
extern ostream clog; ///< Linked to standard error (buffered)
#ifdef _GLIBCXX_USE_WCHAR_T
extern wistream wcin; ///< Linked to standard input
extern wostream wcout; ///< Linked to standard output
extern wostream wcerr; ///< Linked to standard error (unbuffered)
extern wostream wclog; ///< Linked to standard error (buffered)
#endif
///@}
// For construction of filebuffers for cout, cin, cerr, clog et. al.
// When the init_priority attribute is usable, we do this initialization
// in the compiled library instead (src/c++98/globals_io.cc).
#if !(_GLIBCXX_USE_INIT_PRIORITY_ATTRIBUTE \
&& __has_attribute(__init_priority__))
static ios_base::Init __ioinit;
#elif defined(_GLIBCXX_SYMVER_GNU) && defined(__ELF__)
__extension__ __asm (".globl _ZSt21ios_base_library_initv");
#endif
_GLIBCXX_END_NAMESPACE_VERSION
} // namespace
#endif /* _GLIBCXX_IOSTREAM */
istream
ostream
requires_hosted.h
c++config.h
std::ostream
basic_ostream< char > ostream
Base class for char output streams.
Definition iosfwd:145
std::istream
basic_istream< char > istream
Base class for char input streams.
Definition iosfwd:142
std::wostream
basic_ostream< wchar_t > wostream
Base class for wchar_t output streams.
Definition iosfwd:185
std::wistream
basic_istream< wchar_t > wistream
Base class for wchar_t input streams.
Definition iosfwd:182
std
ISO C++ entities toplevel namespace is std.
std::wclog
wostream wclog
Linked to standard error (buffered).
std::wcout
wostream wcout
Linked to standard output.
std::cerr
ostream cerr
Linked to standard error (unbuffered).
std::clog
ostream clog
Linked to standard error (buffered).
std::cout
ostream cout
Linked to standard output.
std::wcin
wistream wcin
Linked to standard input.
std::wcerr
wostream wcerr
Linked to standard error (unbuffered).
std::cin
istream cin
Linked to standard input.