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Write part of a message to a stream asynchronously using a serializer.


Defined in header <boost/beast/http/write.hpp>

    class AsyncWriteStream,
    bool isRequest,
    class Body,
    class Fields,
    class WriteHandler>
    AsyncWriteStream& stream,
    serializer< isRequest, Body, Fields >& sr,
    WriteHandler&& handler);

This function is used to write part of a message to a stream asynchronously using a caller-provided HTTP/1 serializer. The function call always returns immediately. The asynchronous operation will continue until one of the following conditions is true:

This operation is implemented in terms of zero or more calls to the stream's async_write_some function, and is known as a composed operation. The program must ensure that the stream performs no other writes until this operation completes.

The amount of data actually transferred is controlled by the behavior of the underlying stream, subject to the buffer size limit of the serializer obtained or set through a call to http::serializer::limit. Setting a limit and performing bounded work helps applications set reasonable timeouts. It also allows application-level flow control to function correctly. For example when using a TCP/IP based stream.





The stream to which the data is to be written. The type must support the AsyncWriteStream concept.


The serializer to use. The object must remain valid at least until the handler is called; ownership is not transferred.


Invoked when the operation completes. The handler may be moved or copied as needed. The equivalent function signature of the handler must be:

 void handler(
    error_code const& error,        // result of operation
    std::size_t bytes_transferred   // the number of bytes written to the stream

Regardless of whether the asynchronous operation completes immediately or not, the handler will not be invoked from within this function. Invocation of the handler will be performed in a manner equivalent to using boost::asio::io_context::post.

See Also


Convenience header <boost/beast/http.hpp>