But the API name remains the same Don't worry about the name: The original version of this random number generator used the RC4 (also known as ARC4) algorithm. In OpenBSD 5.5 it was replaced with the ChaCha20 cipher, and it may be replaced again in the future as cryptographic techniques advance. A good mnemonic is ``A Replacement Call for Random''. Proposed alternative names: posix_random() or goodrandom()