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

Since C++20

Emits all buffered output and executes any pending flushes, by calling emit() on the underlying std::basic_syncbuf.

# Declarations

void emit();

# Example

#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
    }
}

# See also