init_rs
doc->rs_decoder = init_rs(10, 0x409, FCR, 1, NROOTS);
prz->rs_decoder = init_rs(prz->ecc_info.symsize, prz->ecc_info.poly,
rsc = init_rs(e->symsize, e->genpoly, e->fcs, e->prim, e->nroots);