HierarchyID    string
	ControllerList string
	GroupPath      string
}

// GetCGroups returns a slice of cgroups for pid using fs for filesystem calls.
//
// 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