find_prefixset
struct prefixset *find_prefixset(char *, struct prefixset_head *);
if ((ps = find_prefixset(n->net.psname, &c->prefixsets))
if ((ps = find_prefixset($3, &conf->prefixsets))
if ((ps = find_prefixset($2, &conf->prefixsets))
if (find_prefixset($2, &conf->originsets) == NULL) {
if (find_prefixset(name, sets) != NULL) {