init_session
struct init_session *se_prev;
struct init_session *se_next;
RB_ENTRY(init_session) se_entry;
RB_HEAD(session_tree, init_session) session_tree = RB_INITIALIZER(session_tree);
RB_PROTOTYPE(session_tree, init_session, se_entry, cmp_sessions);
RB_GENERATE(session_tree, init_session, se_entry, cmp_sessions);
struct init_session s;
s = init_session();
struct session * init_session(void);