Usage: ON [#|+|-|^|&|@]WHO [-|^]<parameters> [action]
  This is activated whenever the reply of a /WHO comes in.
  The parameters for the action are as follows:
    $0    The channel the user is on, or 'Channel' for the /who header line.
    $1    Nickname.
    $2    Status. (Here, Gone, *Operator, [ @ChannelOperator ])
    $3    Username (login name)
    $4    Host (host machine)
    $5-   Full Name or other User Data.

See Also:
  ON WHO
