In a GNU/Linux distributions, there are special files
(/dev/random and /dev/urandom) to access the kernel’s random number generator.
- /dev/urandom device returns random bytes using a pseudoran‐
dom number generator seeded from the entropy pool.
- /dev/random device is a legacy interface which dates back to a time
where the cryptographic primitives used in the implementation of
/dev/urandom were not widely trusted.