code: func GetAllSubsystems() ([]string, error) {
  	f, err := os.Open("/proc/cgroups")
  	if err != nil {
  		return nil, err
  	}
  	defer f.Close()
  
  	subsystems := []string{}
  
  	s := bufio.NewScanner(f)
  	for s.Scan() {
  		if err := s.Err(); err != nil {
  			return nil, err
  		}
  		text := s.Text()
  		if text[0] != '#' {
  			parts := strings.Fields(text)
  			if len(parts) >= 4 && parts[3] != "0" {
  				subsystems = append(subsystems, parts[0])
  			}
  		}
  	}
  	return subsystems, nil
  }
docs: // Returns all the cgroup subsystems supported by the kernel