libstdc++-v3/include/std/iostream

   1 // Standard iostream objects -*- C++ -*-
   2
   3 // Copyright (C) 1997-2024 Free Software Foundation, Inc.
   4 //
   5 // This file is part of the GNU ISO C++ Library.  This library is free
   6 // software; you can redistribute it and/or modify it under the
   7 // terms of the GNU General Public License as published by the
   8 // Free Software Foundation; either version 3, or (at your option)
   9 // any later version.
  10
  11 // This library is distributed in the hope that it will be useful,
  12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 // GNU General Public License for more details.
  15
  16 // Under Section 7 of GPL version 3, you are granted additional
  17 // permissions described in the GCC Runtime Library Exception, version
  18 // 3.1, as published by the Free Software Foundation.
  19
  20 // You should have received a copy of the GNU General Public License and
  21 // a copy of the GCC Runtime Library Exception along with this program;
  22 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
  23 // <http://www.gnu.org/licenses/>.
  24
  25 /** @file include/iostream
  26  *  This is a Standard C++ Library header.
  27  */
  28
  29 //
  30 // ISO C++ 14882: 27.3  Standard iostream objects
  31 //
  32
  33 #ifndef _GLIBCXX_IOSTREAM
  34 #define _GLIBCXX_IOSTREAM 1
  35
  36 #pragma GCC system_header
  37
  38 #include <bits/requires_hosted.h> // iostreams
  39
  40 #include <bits/c++config.h>
  41 #include <ostream>
  42 #include <istream>
  43
  44 namespace std _GLIBCXX_VISIBILITY(default)
  45 {
  46 _GLIBCXX_BEGIN_NAMESPACE_VERSION
  47
  48   /**
  49    *  @name Standard Stream Objects
  50    *
  51    *  The `<iostream>` header declares the eight *standard stream objects*.
  52    *  For other declarations, see
  53    *  https://gcc.gnu.org/onlinedocs/libstdc++/manual/io.html
  54    *  and the @link iosfwd I/O forward declarations @endlink
  55    *
  56    *  They are required by default to cooperate with the global C
  57    *  library's `FILE` streams, and to be available during program
  58    *  startup and termination. For more information, see the section of the
  59    *  manual linked to above.
  60   */
  61   ///@{
  62   extern istream cin;           ///< Linked to standard input
  63   extern ostream cout;          ///< Linked to standard output
  64   extern ostream cerr;          ///< Linked to standard error (unbuffered)
  65   extern ostream clog;          ///< Linked to standard error (buffered)
  66
  67 #ifdef _GLIBCXX_USE_WCHAR_T
  68   extern wistream wcin;         ///< Linked to standard input
  69   extern wostream wcout;        ///< Linked to standard output
  70   extern wostream wcerr;        ///< Linked to standard error (unbuffered)
  71   extern wostream wclog;        ///< Linked to standard error (buffered)
  72 #endif
  73   ///@}
  74
  75   // For construction of filebuffers for cout, cin, cerr, clog et. al.
  76   // When the init_priority attribute is usable, we do this initialization
  77   // in the compiled library instead (src/c++98/globals_io.cc).
  78 #if !(_GLIBCXX_USE_INIT_PRIORITY_ATTRIBUTE \
  79       && __has_attribute(__init_priority__))
  80   static ios_base::Init __ioinit;
  81 #elif defined(_GLIBCXX_SYMVER_GNU) && defined(__ELF__)
  82   __extension__ __asm (".globl _ZSt21ios_base_library_initv");
  83 #endif
  84
  85 _GLIBCXX_END_NAMESPACE_VERSION
  86 } // namespace
  87
  88 #endif /* _GLIBCXX_IOSTREAM */