tropy(category13-admin-isp-software.html) - phpMan

getentropy (3)       - fill a buffer with random bytes
RAND_DRBG_cleanup_entropy_fn (3ssl) - set callbacks for reseeding
RAND_DRBG_get_entropy_fn (3ssl) - set callbacks for reseeding
RAND_egd (3ssl)      - query entropy gathering daemon
RAND_egd_bytes (3ssl) - query entropy gathering daemon
RAND_query_egd_bytes (3ssl) - query entropy gathering daemon