// The expected cgroup format is "hierarchy-ID:controller-list:cgroup-path", and
// this function will return an error if every cgroup does not meet that format.
//
// For more information, see:
//   - http://man7.org/linux/man-pages/man7/cgroups.7.html
//   - https://www.kernel.org/doc/Documentation/cgroup-v2.txt
func GetCgroups(procCgroupData bytes.Buffer) ([]Cgroup, error) {
	reader := bytes.NewReader(procCgroupData.Bytes())
	var cgroups []Cgroup

	}

	// Only interested in flushing the size_t not mtime/atime
	if err = Fdatasync(w); err != nil {
		w.Close()
		return err
	}

	// Dealing with error returns from close() - 'man 2 close'
	//
	// A careful programmer will check the return value of close(), since it is quite possible that
	// errors on a previous write(2) operation are reported only on the final close() that releases