[sudo-users] Displaying errors to users

[seph]

In my environment, users have a large set of whitelisted commands, and
everything else is denied by default.

For usability sake, I'd like sudo to tell them when something is denied.
It does exit with an error code of 1, but that's pretty subtle.

I notice that sudo will error if the command is blocked, so I can hack
something with: 
> ALL ALL=(ALL:ALL) NOPASSWD: !ALL
> %group ALL=(ALL:ALL) NOPASSWD: COMMAND_LIST

But I'm hoping there's something cleaner.

help?

-- 
  seph
  seph at directionless.org