Hacker News Reader

Comment by bartvk | Hacker News Reader

I remember reading the BOFH series (Bastard Operator From Hell), where a horrible sysadmin would back up to null, because it was so efficient.

View on HN

Everything sent to /dev/null can eventually be retrieved from /dev/random, given sufficient time.

However, since you're effectively brute forcing a match on an unknown key, the universe may go cold and dark before your content arises, for any content larger than 128 bits or so.

And at some point it gets more efficient to just wait until the universe randomly starts to repeats itself to recreate the content you wanted.

But you’ll restart with it in not-yet-lost-it state and will lose it eventually. There is nothing useful in /dev/random, really, apart from the entropy for crypto. Trillions of trillions of … of trillions unique virtual atoms of no particular value.

Only if you believe that /dev/random is truly random.

Even a truly random die is not guaranteed to ever roll a 6.

Though it does eventually roll a 6 almost always.

Which is math speak for 100% of the time.

“ever” implies the limit of time. Since lim_{t->Inf} p(at least one 6 is rolled) = 1, I think you could say it’s guaranteed.

Yet, it probably will.

if it has once, it will again

https://en.wikipedia.org/wiki/Poincar%C3%A9_recurrence_theor...

I KNOW WHERE the data you read from /dev/random COMES FROM.

But I can't tell you because I would be a dead man if I would.

it's written on the menu of the restaurant at the end of the universe

Yeah, I remember that, too. :) I think I read that even before I first tried Linux.

Reply on news.ycombinator.com