https://www.ietf.org/rfc/rfc4122.txt is the reference for official UUIDs. This implementation provides a version 1 UUID that includes both the Erlang pid identifier (ID, Serial, Creation) and the distributed Erlang node name within the 48 bit node ID. To make room for the Erlang pid identifier, the 48 bits from the MAC address (i.e., 3 OCI (Organizationally Unique Identifier) bytes and 3 NIC (Network Interface Controller) specific bytes) and the distributed Erlang node name are bitwise-XORed down to 16 bits. The Erlang pid is bitwise-XORed from 72 bits down to 32 bits. The version 3 (MD5), version 4 (random), and version 5 (SHA) methods are provided as specified within the RFC.

Requires Erlang >= R16B01

Certain uuid functions require initializing the Erlang process before the function is called. The initialization ensures the quickrand dependency is able to provide randomness for the uuid module use.

If you use the functions uuid:new/1, uuid:new/2 or uuid:get_v4_urandom/0, you should call the function quickrand:seed/0 or quickrand:seed/1 first.

If you use the function uuid:get_v4/1 with a cached argument, you should call the function quickrand_cache:init/0 or quickrand_cache:init/1 first. If you use the function uuid:get_v4/1 with quickrand_cache state, you would have called the function quickrand_cache:new/0 or quickrand_cache:new/1 first. Using the quickrand_cache init function means cached random data is stored in the process dictionary and using the quickrand_cache new function (instead of init) means cached random data is kept in a state variable.

rebar get-deps
rebar compile

Michael Truog (mjtruog at protonmail dot com)

MIT License