yp_maplist
int yp_maplist(char *indomain, struct ypmaplist **outmaplist);
r = yp_maplist(domain, &ypml);
static void yp_maplist_free(struct ypmaplist *yp_maplist)
while (yp_maplist) {
next = yp_maplist->next;
free(yp_maplist->map);
free(yp_maplist);
yp_maplist = next;
struct ypmaplist *yp_maplist = NULL;
yp_maplist_free(yp_maplist);
yp_maplist_free(yp_maplist);
cur->next = yp_maplist;
yp_maplist = cur;
yp_error("map: %s", yp_maplist->map);
return(yp_maplist);