topo_scheme_info_t
walk_schemes_cb(topo_hdl_t *thp, const topo_scheme_info_t *info, void *arg)
typedef int (*topo_scheme_walk_cb_f)(topo_hdl_t *, const topo_scheme_info_t *,
topo_scheme_info_t info;
topo_scheme_info_t info;