Could be. This was on a Mac, around 2013, so it should have been pretty snappy.
Whatever it got I never noticed. Maybe it was trawling through a bunch of build detritus in `~/.cpan` or something.
I accidentally did the same on my Mac via a shell script where I assumed mktemp worked the same as gnu mktemp, it does not. IIRC it was my /Applications directory that was first to be hit; most of the directory was unaffected due to file permissions but it did delete some files despite me catching thee error and sending sigkill within seconds.