int unit_load_fragment_and_dropin(Unit *u);
int unit_load_fragment_and_dropin_optional(Unit *u);
-int unit_load_nop(Unit *u);
int unit_load(Unit *unit);
const char *unit_description(Unit *u);
Unit *unit_following(Unit *u);
-const char *unit_type_to_string(UnitType i);
-UnitType unit_type_from_string(const char *s);
-
const char *unit_load_state_to_string(UnitLoadState i);
UnitLoadState unit_load_state_from_string(const char *s);