Write some data to the stream.

template<
    class ConstBufferSequence>
std::size_t
write_some(
    ConstBufferSequence const& buffers,
    boost::system::error_code& ec);

This function is used to write data on the stream. The function call will block until one or more bytes of data has been written successfully, or until an error occurs.

The number of bytes written. Returns 0 if an error occurred.

The write_some operation may not transmit all of the data to the peer. Consider using the net::write function if you need to ensure that all data is written before the blocking operation completes.