std::basic_osyncstream<CharT,Traits,Allocator>::emit

 

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std::basic_osyncstream

公有成员函数

basic_osyncstream::basic_osyncstream (C++20)

basic_osyncstream::operator= (C++20)

basic_osyncstream::~basic_osyncstream (C++20)

basic_osyncstream::rdbuf (C++20)

basic_osyncstream::get_wrapped (C++20)

basic_osyncstream::emit (C++20)

 

void emit();

通过调用底层 std::basic_syncbuf 上的 emit()，发出所有缓冲的输出并执行任何待处理的刷新操作。

参数

(无)

示例

运行此代码

#include <iostream>
#include <syncstream>
 
int main()
{
    {
        std::osyncstream bout(std::cout);
        bout << "Hello," << '\n'; // no flush
        bout.emit(); // characters transferred; cout not flushed
        bout << "World!" << std::endl; // flush noted; cout not flushed
        bout.emit(); // characters transferred; cout flushed
        bout << "Greetings." << '\n'; // no flush
    } // destructor calls emit(): characters transferred; cout not flushed
 
    // emit can be used for local exception-handling on the wrapped stream
    std::osyncstream bout(std::cout);
    bout << "Hello, " << "World!" << '\n';
    try
    {
        bout.emit();
    }
    catch (...)
    {
        // handle exceptions
    }
}

输出

Hello,
World!
Greetings.
Hello, World!

另请参见

(析构函数)	销毁 basic_osyncstream 并发出其内部缓冲区 (公有成员函数)
emit	将整个内部缓冲区原子地传输到包装的 streambuf (std::basic_syncbuf<CharT,Traits,Allocator> 的公有成员函数)