func receiveFile(r io.Reader, targetFile, resForkFile, infoFork, counterWriter io.Writer) error {
var ffo flattenedFileObject
if _, err := ffo.ReadFrom(r); err != nil {
func receiveFile(r io.Reader, targetFile, resForkFile, infoFork, counterWriter io.Writer) error {
var ffo flattenedFileObject
if _, err := ffo.ReadFrom(r); err != nil {