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Write some message data asynchronously.

    class ConstBufferSequence,
    class WriteHandler>
    bool fin,
    ConstBufferSequence const& buffers,
    WriteHandler&& handler);

This function is used to asynchronously write part of a message. This call always returns immediately. The asynchronous operation will continue until one of the following conditions is true:

The algorithm, known as a composed asynchronous operation, is implemented in terms of calls to the next layer's async_write_some function. The program must ensure that no other calls to websocket::stream::write, websocket::stream::write_some, websocket::stream::async_write, or websocket::stream::async_write_some are performed until this operation completes. If this is the beginning of a new message, the message opcode will be set to text or binary based on the current setting of the websocket::stream::binary (or websocket::stream::text) option. The actual payload sent may be transformed as per the WebSocket protocol settings.





true if this is the last part of the message.


The buffers containing the message part to send. The implementation will make copies of this object as needed, but ownership of the underlying memory is not transferred. The caller is responsible for ensuring that the memory locations pointed to by buffers remains valid until the completion handler is called.


The completion handler to invoke when the operation completes. The implementation takes ownership of the handler by performing a decay-copy. The equivalent function signature of the handler must be:

void handler(
    error_code const& ec,           // Result of operation
    std::size_t bytes_transferred   // Number of bytes sent from the
                                    // buffers. If an error occurred,
                                    // this will be less than the buffer_size.

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 net::post.