TinTin++ Mud Client Manual
         SNOOP

Command: #snoop {session name} {on|off}

         If there are multiple sessions active, this command allows you to monitor
         what is going on in the sessions that are not currently active.  The
         line of text from other sessions will be prefixed by the session's name.

         You can toggle off snoop mode by executing #snoop a second time.

Related: all, port, run, session, sessionname, ssl and zap.