int show_cgroup_by_path(const char *path, const char *prefix, unsigned columns, OutputFlags flags);
int show_cgroup(const char *controller, const char *path, const char *prefix, unsigned columns, OutputFlags flags);
-int show_cgroup_and_extra_by_spec(const char *spec, const char *prefix, unsigned n_columns, const pid_t extra_pids[], unsigned n_extra_pids, OutputFlags flags);
int show_cgroup_and_extra(const char *controller, const char *path, const char *prefix, unsigned n_columns, const pid_t extra_pids[], unsigned n_extra_pids, OutputFlags flags);
int show_cgroup_get_unit_path_and_warn(