[wiredfool]

Looking at man shred, apparently one can shred stdout.

[brudgers]

"Shredding stdout" sounds like the highest complement for a command line utility.

[gcr]

Why not? One can shred any file descriptor. :-)

I bet one could even shred a network socket.

[emodendroket]

Is there any advantage to specifically disabling that?

[dTal]

And yet it doesn't "work":

  dtal@reepicheep:~$ cat /dev/urandom | shred -
  shred: -: invalid file type

[colanderman]

Your command points stdin to the output of some random command. Even if you actually redirected stdout (pipe to cat, not from), it still wouldn't work, because cat's stdin isn't a file.

You need to point stdout to an actual file, like this:

    shred > /my/secret/file.txt

Why would you do this? At the end of a long batch of commands that all write to some temporary file opened on stdout. Not uncommon in shell-land.