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PONG(1)         MISCELLANEOUS NETWORK SUPPORT COMMANDS       PONG(1)
PENIX               OPERATING SYSTEM DOCUMENTATION             PENIX
 
NAME
     pong - net-broadcast restart message
 
SYNOPSIS
     pong [ - ] adnpv [ count ] [ delay ] [ path ]
 
DESCRIPTION
     Pong  broadcasts  a  general  `Hey, I'm here!'  message to any
     other machines on the network.   The  exact  contents  of  the
     message packet depend on  whether the machine in question is a
     Dom_Master  or  a  Sub_Server.  Pong waits for acknowledgement
     from, by default, one machine; it can be specified to wait for
     responses from up to 255 machines before resuming.  Which is a
     pretty  pointless feature  when you think about it, but it was
     piss-easy to implement, so we did.
 
 
FUNCTION LETTERS
 
     a    acknowledge-count.  If not specified, this defaults to one.
          It  can  be  set to zero,  in case  the machine is not on a
          network...  but  if the machine  isn't  on a network,  then
          there really isn't any point in PONGing in the first place,
          is there?   The upper limit is 255, which is also the limit
          of Dom/Sub relationships  allowed for any single Net_Clique
          of machines.
 
     d    Delay.  If specified, the machine will wait for this number
          of  ticks before  returning a -1 errorcode and exiting.  If
          not specified,  the  machine  will wait until it receives a
          response from another machine,  unto  eternity (or the next
          reset).
 
     n    Notify.  This  notifies the users that a Pong has just been
          issued.  If any  of  them  are  logged  in as the rooted(c)
          user, they may receive responses from other machines,  such
          as  `Phwooaaaaar!',  `Who did THAT?', `Jesus, that STINKS!'
          and (most frequently) `Ahhhh, SHADDUP!'
 
     p    Specify  alternate  packet.  Generally,  the packet sent by
          pong is determined by  the machine's Net-status (either Dom
          or Sub);  mild  variations are available, but on no account
          should a Sub_Server  attempt  to issue a Dom_Master packet,
          because  it  makes  the  actual  Dom feel inadequate.  This
          option requires  the specification of a file which contains
          the alternate packet to use.
 
     v    Verbose  mode.   If this option is absent,  you will see no
          response  to  the  command after execution.  Otherwise, the
          machine  will  echo  its  pong-text  on the console and any
          responses  to  it  from  other  machines,  along with their
          net-addresses.
 
EXAMPLES
 
      To  send  an  alternate packet structure, display responses and
      resume after four responses have been detected:
 
         pong apv 4 /uselss/all_kindsa_stuff/pongpacket2
 
      PONGing net:
 
      [  sub:harry_as_a_boy>>Galoot_Cologne     03F21AC4E2D1  ]
      [                                                       ]
      [  hi there, this is sub:harry_as_a_boy>>Galoot_Cologne,]
      [  i was down for an hour there because my operators    ]
      [  wanted to try out the cfts command, but i'm back     ]
      [  up now!  did anyone miss me?  :->                    ]
      [                                                       ]
 
      waiting for reponses:
 
      *** from sub:kanttner>>jefferson:
      [  go away harry you smelly little nonentity ]
 
      *** from dom:slick>>jefferson:
      [  piss off. ]
 
      *** from sub:Mammy_Nun>>galoot_cologne:
      [  we heard you de FIRSE time, okay? ]
 
      *** from dom:rhonda>>galoot_cologne:
      [  HARRYYYY, you are nothing but a WORRRRRRRRRRRRM! ]
 
 
FILES
 
/uselss/all_kindsa_stuff       Repository for alternate message
                               packets.  The default is called
                               `default'.
 
/uselss/little_black_book  
    Current LBB network list, containing
                               binary addresses of the other members
                               of the Clique.  Note: this file can
                               only be updated by the Clique's Dom.
                               This also contains the addresses of
                               any other Cliques on the network.
 
SEE ALSO
     bollx(1), stuffio(2), doobrie(9), brap(12), yoohoo(2),
     LBB_lookup(1), cftn(2) LBB_init(3), LBB_re_init(1), LBB_kick(1)
 
BUGS
 
     If there are no entries in /uselss/little_black_book,  or if the
     machine is not part of a Dom/Sub network (i.e. stand-alone), the
     command will  enter a tight recursive loop,  gradually consuming
     more and more CPU time until  the system either stops completely
     or  until one  of  the  caenobite  processes  gets  annoyed  and
     terminates   it.   This  can  be  dangerous,  as  the  caenobite
     processes are none too  discriminating  and  may take out one or
     two other processes along the way.  They seem to have a fondness
     for  anything  running on the system console, like the rooted(c)
     session.
 
     The n option can be slow.
 
     If  there  are  Dom-ID  packets in  the /uselss/all_kindsa_stuff
     directory of a Sub machine,  there are no mechanisms in place to
     ensure  that  the  operator  does  not  PONG  the net with a Dom
     packet.  This will upset the carefully-orchestrated hierarchy of
     the net,  causing  the  Subs to have to choose between two Doms.
     As soon as  the  Subs see a Dom-ID packet  from a machine,  they
     assume that it IS a Dom, and a moebius-hoffstaedter loop arising
     from a Sub trying  to satisfy conflicting requests from two Doms
     becomes a possibility.   This can bring down the entire net, and
     thus should be avoided,  unless the net needs to be brought down
     quickly, in which case refer to cftn(2).
 
     There  is  still  no  way  selectively to follow symbolic links.
     And to be brutally honest, we  don't  think there will be in the
     immediate future.

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Sunburne Computer, Inc. 9 October 1991
© nikolai@ariel.ucs.unimelb.edu.au. Last update: Sunday, June 16, 1996