return err
			}
			perm = info.Mode() & os.ModePerm
		}

		// Always copy directories (don't symlink them).
		// If we add a file in the overlay, we don't want to add it in the original.
		if info.IsDir() {
			return os.MkdirAll(dstPath, perm|0200)
		}

		// If the OS supports symlinks, use them instead of copying bytes.
		if err := os.Symlink(srcPath, dstPath); err == nil {
			return nil
		}