code: public void writeByteBufferPart(byte[] buffer, int offset, int length)
          throws IOException
      {
          while (length > 0) {
              flushIfFull();
  
              int sublen = _buffer.length - _offset;
  
              if (length < sublen)
                  sublen = length;
  
              _buffer[_offset++] = BC_BINARY_CHUNK;
              _buffer[_offset++] = (byte) (sublen >> 8);
              _buffer[_offset++] = (byte) sublen;
  
              System.arraycopy(buffer, offset, _buffer, _offset, sublen);
  
              _offset += sublen;
              length -= sublen;
              offset += sublen;
          }
      }
docs: Writes a byte buffer to the stream.
  
  <code><pre>
  b b16 b18 bytes
  </pre></code>