// with files in it. Returns nil for a non-empty directory even when
// recursive is set to false.
func (s *xlStorage) deleteFile(basePath, deletePath string, recursive, immediate bool) error {
	if basePath == "" || deletePath == "" {
		return nil
	}

	bp := pathutil.Clean(basePath) // do not override basepath / or deletePath /
	dp := pathutil.Clean(deletePath)
	if !strings.HasPrefix(dp, bp) || dp == bp {
		return nil
	}

pkg go/build, type Context struct, GOPATH string
pkg go/build, type Context struct, GOROOT string
pkg go/build, type Context struct, HasSubdir func(string, string) (string, bool)
pkg go/build, type Context struct, IsAbsPath func(string) bool
pkg go/build, type Context struct, IsDir func(string) bool
pkg go/build, type Context struct, JoinPath func(...string) string
pkg go/build, type Context struct, OpenFile func(string) (io.ReadCloser, error)