int manager_get_session_by_cgroup(Manager *m, const char *cgroup, Session **session);
int manager_get_session_by_pid(Manager *m, pid_t pid, Session **session);
int manager_get_session_by_cgroup(Manager *m, const char *cgroup, Session **session);
int manager_get_session_by_pid(Manager *m, pid_t pid, Session **session);