Posts

This is the second post in a series. See the previous one here.

Things are looking grim. We do not have much to work with. But there is still hope!

One thing you may have noticed if you're following along in the simulator is that once everything gets blown away, you still have your ssh connection, and you can still try to run commands. Most of them will reply with a command not found message, but at least something is still alive to print that!

How does that happen if we deleted everything?

My beautiful binaries! (With apologies to Eric Rosen)

Yesterday a friend came to me with a problem. While managing some backups, he accidentally deleted /bin, /boot, /dev, /tmp, /srv, /usr, and /opt from the filesystem itself instead of the backups.

This left an interesting problem: without the binaries from /bin and /usr, it was impossible to do almost everything you normally do. Picture the situation. You do not have a head or a tail, let alone an entire cat! No chmod, certainly nothing fancy like curl or sshd. If you listen closely though, you might hear an echo...

In 1777, Georges-Louis Leclerc, Comte de Buffon posed the following question:

Suppose we have a floor made of parallel wooden boards, each the same width, and we drop a needle onto the floor. What is the probability that the needle will lie across a line between two boards?

He solved it with some fancy calculus, which is a fine way of doing it, but not particularly satisfying to me. However in 1860 a man named Joseph-Émile Barbier came up with this super slick proof, which is without a doubt the coolest proof I've ever seen.