pkg/ioutil/readcloser.go
func NewExactReadCloser(rc io.ReadCloser, totalBytes int64) io.ReadCloser {
	return &exactReadCloser{rc: rc, totalBytes: totalBytes}
}
func NewExactReadCloser(rc io.ReadCloser, totalBytes int64) io.ReadCloser {
	return &exactReadCloser{rc: rc, totalBytes: totalBytes}
}
func NewExactReadCloser ( rc io . ReadCloser , totalBytes int64 ) io . ReadCloser { return & exactReadCloser { rc : rc , totalBytes : totalBytes } }
// NewExactReadCloser returns a ReadCloser that returns errors if the underlying
// reader does not read back exactly the requested number of bytes.
NewExactReadCloser returns a ReadCloser that returns errors if the underlying reader does not read back exactly the requested number of bytes .