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@fgaz At a job long in the past, I had a coworker who was very enamored of a particular do-everything Python library which I will not name at this time. This library included some built-in logging facilities, but he didn't actually need the log for the thing he was making, so he set it to log to `/dev/null`.

It turns out that this library had automatic log rotation built in. The way it worked was that it kept track of the number of bytes written to a log, and when it crossed a certain threshold, it would rename the file it was logging to, and open a new log file.

Unfortunately, the thing my coworker built ran as `root`. It started up and ran fine for a while, merrily logging to `/dev/null` as instructed. After a while, though, it noticed "oh hey I've written more than a megabyte of logs, time to rotate the log file" - it then renamed `/dev/null` to `/dev/null.YYYY-mm-dd.HH:MM:SS` and created a new `/dev/null` that was just a regular text file. From that point onward, anything that got written to `/dev/null` actually got written to disk. Chaos ensued.

That one took a whole day to figure out...