func copyFile(rFile, lFile uri.Uri) (io.ReadCloser, io.WriteCloser) { var err error lFd, err := lFile.OpenRead() for { if err != nil { time.Sleep(time.Second * 1) } else { break } lFd, err = lFile.OpenRead() } rFd, err := rFile.OpenWrite() for { if err != nil { time.Sleep(time.Second * 1) } else { break } rFd, err = rFile.OpenWrite() } io.Copy(rFd, lFd) return lFd, rFd }