ossl_rand_pool_length
ret = ossl_rand_pool_length(pool);
ret = ossl_rand_pool_length(pool);
ossl_rand_pool_length(pool),
size_t ossl_rand_pool_length(RAND_POOL *pool);
memcpy(out, ossl_rand_pool_buffer(pool), ossl_rand_pool_length(pool));
ret = ossl_rand_pool_length(pool);
memcpy(out, ossl_rand_pool_buffer(pool), ossl_rand_pool_length(pool));
ret = ossl_rand_pool_length(pool);