cs_set_socket_event_mask
static int cs_set_socket_event_mask(cs_socket_t *, unsigned);
(void) cs_set_socket_event_mask(sp, cs_merge_event_masks(sp, client));
(void) cs_set_socket_event_mask(sp, cs_merge_event_masks(sp, client));
(void) cs_set_socket_event_mask(sp, cs_merge_event_masks(sp, client));