typedef int (*sd_rtnl_message_handler_t)(sd_rtnl *rtnl, sd_rtnl_message *m, void *userdata);
/* bus */
-int sd_rtnl_open(sd_rtnl **nl, uint32_t groups);
+int sd_rtnl_open(sd_rtnl **nl, unsigned n_groups, ...);
sd_rtnl *sd_rtnl_ref(sd_rtnl *nl);
sd_rtnl *sd_rtnl_unref(sd_rtnl *nl);
int sd_rtnl_message_open_container_union(sd_rtnl_message *m, unsigned short type, const char *key);
int sd_rtnl_message_close_container(sd_rtnl_message *m);
-int sd_rtnl_message_read_string(sd_rtnl_message *m, unsigned short type, char **data);
+int sd_rtnl_message_read_string(sd_rtnl_message *m, unsigned short type, const char **data);
int sd_rtnl_message_read_u8(sd_rtnl_message *m, unsigned short type, uint8_t *data);
int sd_rtnl_message_read_u16(sd_rtnl_message *m, unsigned short type, uint16_t *data);
int sd_rtnl_message_read_u32(sd_rtnl_message *m, unsigned short type, uint32_t *data);