/dev/null

Thus,

Recreating /dev/null

The following mv command overwrites /dev/null:

$ sudo mv a-file /dev/null

Now, /dev/null is not the special device file anymore.

It can be recreated again by first deleting the ordinary file whose name now is /dev/null …

$ sudo rm /dev/null

… and then recreating it like so:

$ sudo mknod -m 0666 /dev/null c 1 3