标准库头文件 <syncstream>

 

C++

语言

标准库头文件

自立与有宿主实现

具名要求

语言支持库

概念库 (C++20)

诊断库

工具库

字符串库

容器库

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范围库 (C++20)

算法库

数值库

输入/输出库

本地化库

正则表达式库 (C++11)

原子操作库 (C++11)

线程支持库 (C++11)

文件系统库 (C++17)

技术规范

 

标准库头文件

语言支持
<cstddef> <limits> <climits> <coroutine>	<cfloat> <cstdint> <new> <source_location>	<typeinfo> <exception> <initializer_list> <version>	<csignal> <csetjmp> <cstdarg>
概念
<concepts>
诊断
<stdexcept>	<cassert>	<cerrno>	<system_error>
通用工具
<utility> <memory> <memory_resource> <scoped_allocator>     <compare>	<bitset> <tuple> <optional> <any> <variant>	<type_traits> <ratio> <chrono> <typeindex> <functional>	<ctime> <cstdlib>
字符串
<string> <string_view> <cstring>	<charconv> <format>	<cctype> <cwctype>	<cwchar> <cuchar>
本地化
<locale>	<codecvt>	<clocale>
容器
<span> <array> <vector>	<deque> <forward_list> <list>	<map> <set> <queue>	<unordered_map> <unordered_set> <stack>
迭代器
<iterator>
范围
<ranges>
算法
<algorithm>	<execution>
数值
<complex> <random>	<valarray> <numeric>	<bit> <numbers>	<cfenv> <cmath>
输入/输出
<iosfwd> <ios> <iomanip> <streambuf>	<istream> <ostream> <iostream>	<sstream> <fstream> <syncstream>	<cstdio> <cinttypes> <strstream>
正则表达式
<regex>
文件系统
<filesystem>
线程支持
<thread> <atomic> <mutex>	<shared_mutex> <condition_variable> <future>	<stop_token> <semaphore>	<latch> <barrier>
C 兼容
<ciso646> <cstdalign>	<cstdbool> <ccomplex>	<ctgmath>

 

此头文件是输入/输出库的一部分。

包含
<ostream>
类
basic_syncbuf (C++20)	同步输出设备的包装 (类模板)
basic_osyncstream (C++20)	同步输出流的包装 (类模板)
typedef
syncbuf	basic_syncbuf<char>
wsyncbuf	basic_syncbuf<wchar_t>
osyncstream	basic_osyncstream<char>
wosyncstream	basic_osyncstream<wchar_t>
函数
std::swap(std::basic_syncbuf) (C++20)	特化 std::swap 算法 (函数模板)

概要

namespace std {
template <class CharT,
          class Traits = char_traits<CharT>,
          class Allocator = allocator<CharT>>
  class basic_syncbuf;
 
using syncbuf  = basic_syncbuf<char>;
using wsyncbuf = basic_syncbuf<wchar_t>;
 
template <class CharT,
          class Traits = char_traits<CharT>,
          class Allocator = allocator<CharT>>
  class basic_osyncstream;
 
using osyncstream  = basic_osyncstream<char>;
using wosyncstream = basic_osyncstream<wchar_t>;
 
template <class CharT, class Traits, class Allocator>
  void swap( std::basic_syncbuf<CharT, Traits, Allocator>& lhs,
             std::basic_syncbuf<CharT, Traits, Allocator>& rhs );
 
}

类 std::basic_syncbuf

template <class CharT,
          class Traits = char_traits<CharT>,
          class Allocator = allocator<CharT>>
class basic_syncbuf
  : public basic_streambuf<CharT, Traits> {
 
public:
  using char_type      = CharT;
  using int_type       = typename Traits::int_type;
  using pos_type       = typename Traits::pos_type;
  using off_type       = typename Traits::off_type;
  using Traits_type    = Traits;
  using allocator_type = Allocator;
 
  using streambuf_type = basic_streambuf<CharT, Traits>;
 
  // 构造函数/析构函数：
  explicit
  basic_syncbuf(streambuf_type* obuf = nullptr)
    : basic_syncbuf(obuf, Allocator()) {}
  basic_syncbuf(streambuf_type*, const Allocator&);
  basic_syncbuf(basic_syncbuf&&);
  ~basic_syncbuf();
 
  // 赋值/交换：
  basic_syncbuf& operator=(basic_syncbuf&&);
  void swap(basic_syncbuf &);
 
  // 成员：
  bool emit();
  streambuf_type* get_wrapped()   const noexcept;
  allocator_type  get_allocator() const noexcept;
  void            set_emit_on_sync(bool) noexcept;
 
protected:
  // 覆盖的虚函数：
  int sync() override;
 
private:
  streambuf_type *wrapped;       // 仅用于阐释
  bool            emit_on_sync{};// 仅用于阐释
};

类 std::basic_osyncstream

template <class CharT,
          class Traits = char_traits<CharT>,
          class Allocator = allocator<CharT>>
class basic_osyncstream
  : public basic_ostream<CharT, Traits>
{
public:
  using char_type      = CharT;
  using int_type       = typename Traits::int_type;
  using pos_type       = typename Traits::pos_type;
  using off_type       = typename Traits::off_type;
  using Traits_type    = Traits;
  using allocator_type = Allocator;
  using streambuf_type = basic_streambuf<CharT, Traits>;
  using syncbuf_type   = basic_syncbuf<CharT, Traits, Allocator>;
 
  // 构造函数/析构函数：
  basic_osyncstream(streambuf_type *, const Allocator &);
  explicit basic_osyncstream(streambuf_type *obuf)
    : basic_osyncstream(obuf, Allocator()) {}
  basic_osyncstream(basic_ostream<CharT,Traits> &os, const Allocator &allocator)
    : basic_osyncstream(os.rdbuf(), allocator) {}
  explicit basic_osyncstream(basic_ostream<CharT,Traits> &os)
    : basic_osyncstream(os, Allocator()) {}
  basic_osyncstream(basic_osyncstream&&) noexcept;
  ~basic_osyncstream();
 
  // 赋值：
  basic_osyncstream& operator=(basic_osyncstream&&) noexcept;
 
  // 成员：
  void emit();
  streambuf_type* get_wrapped() const noexcept;
  syncbuf_type* rdbuf() const noexcept { return &sb ; }
 
private:
  syncbuf_type sb; // 仅用于阐释
};