// Blocks will read this much and find the first following newline.
// 128KB appears to be a very reasonable default.
const csvSplitSize = 128 << 10

// startReaders will read the header if needed and spin up a parser
// and a number of workers based on GOMAXPROCS.
// If an error is returned no goroutines have been started and r.err will have been set.
func (r *Reader) startReaders(newReader func(io.Reader) *csv.Reader) error {

			src:      r,
			md5:      NewUUIDHash(forceMD5),
			checksum: etag,
		}
	}
	return &Reader{
		src:      r,
		md5:      md5.New(),
		checksum: etag,
	}
}

// Read reads up to len(p) bytes from the underlying
// io.Reader as specified by the io.Reader interface.
func (r *Reader) Read(p []byte) (int, error) {
	n, err := r.src.Read(p)
	r.readN += int64(n)
	r.md5.Write(p[:n])