N2RNG_INITIALIZED
#define n2rng_setinitialized(n2rng) ((n2rng)->n_flags |= N2RNG_INITIALIZED)
#define n2rng_clrinitialized(n2rng) ((n2rng)->n_flags &= ~N2RNG_INITIALIZED)
#define n2rng_isinitialized(n2rng) ((n2rng)->n_flags & N2RNG_INITIALIZED)