undef _$_F_O_U_N_D;
if (_$_V_E_C_T_O_R =~ /[^\000]/) {
    for (length($`)*8..length($`)*8+7) {
	_$_F_O_U_N_D = $_, last if vec(_$_V_E_C_T_O_R,$_,1);
    }
}
