.. efun:: object snoop(object snooper)
  object snoop(object snooper, object snoopee)

  Starts a snoop from :arg:`snooper` on :arg:`snoopee`, or if :arg:`snoopee` is not given, terminates any snoop from :arg:`snooper`.

  Return :arg:`snoopee` on success, or 0 for a failure (including snooping loops).

  The snoop is checked with the master object for validity. It will also fail if a snoop would result in a recursive snoop action.

  :arg:`snooper` can be an interactive player or an object. If it is an interactive player, the snooped text is prepended with a '%' and sent directly to the player's connection. If :arg:`snooper` is an object, the snooped text is sent in two calls to the object's :applied:`catch_tell` lfun: the first call passes just the "%" (plus the prompt if the object changed it), the second the actual text.

  .. seealso:: :efun:`query_snoop`, :applied:`catch_tell`