map_unset
ans1 = map_unset(&rpcbreg, rpcbreg.r_owner);
ans2 = map_unset(&rpcbreg, rpcbreg.r_owner);
ans = map_unset(regp, getowner(transp, owner, sizeof owner));
(void)map_unset(®, rpcbind_superuser);
bool_t map_unset(RPCB *, const char *);