# File lib/mongo/grid/stream/write.rb, line 83
          def write(io)
            ensure_open!
            @indexes ||= ensure_indexes!
            @length += io.size
            chunks = File::Chunk.split(io, file_info, @n)
            @n += chunks.size
            chunks_collection.insert_many(chunks) unless chunks.empty?
            self
          end