resource helper(id, nap_time : int)
   write("helper", id, "is alive, nap_time=", nap_time)

   process help
      var napping : int
      do true ->
         napping := int(random(1000*nap_time))
         writes("age=", age(), ", helper ", id,
           " is napping for ", napping, "ms\n")
         nap(napping)
      od
   end help
end helper

resource user()
   import helper
   var num_helpers : int := 5, nap_time : int := 3, run_time : int := 60
   getarg(1, num_helpers); getarg(2, nap_time); getarg(3, run_time)

   write("resource user starting,", num_helpers, "helpers,",
      nap_time, "napping time,", run_time, "running time")

   var machine_name : string[64]         # added code starts HERE #####
   var machine_cap[1:num_helpers] : cap vm
   fa i := 1 to num_helpers ->
      getarg(3+i, machine_name)
      machine_cap[i] := create vm() on machine_name
      if machine_cap[i] = null ->
         write("Cannot create vm on", machine_name, "so aborting"); stop
      fi
      write("Virtual machine starting up on machine", machine_name)
   af                                    # added code ends HERE except ...

   fa i := 1 to num_helpers -> create helper(i, nap_time)
         on machine_cap[i]               # ... for this line HERE
   af
   nap(1000*run_time); write("must stop now"); stop
end user

/* ............... Example compile and run(s)

% sr -o multiple_machines multiple_machines.sr
% ./multiple_machines 3 2 10 violet lily rose
resource user starting, 3 helpers, 2 napping time, 10 running time
Virtual machine starting up on machine violet
Virtual machine starting up on machine lily
Virtual machine starting up on machine rose
helper 1 is alive, nap_time= 2
helper 2 is alive, nap_time= 2
helper 3 is alive, nap_time= 2
age=210, helper 3 is napping for 1995ms
age=4010, helper 1 is napping for 1029ms
age=1710, helper 2 is napping for 1938ms
age=5040, helper 1 is napping for 181ms
age=5260, helper 1 is napping for 1503ms
age=3650, helper 2 is napping for 940ms
age=2210, helper 3 is napping for 1614ms
age=6880, helper 1 is napping for 1776ms
age=4590, helper 2 is napping for 396ms
age=4990, helper 2 is napping for 1523ms
age=3830, helper 3 is napping for 1431ms
age=8750, helper 1 is napping for 78ms
age=8830, helper 1 is napping for 865ms
age=6520, helper 2 is napping for 1514ms
age=5270, helper 3 is napping for 1854ms
age=9710, helper 1 is napping for 1178ms
age=8040, helper 2 is napping for 431ms
age=8480, helper 2 is napping for 1002ms
age=10950, helper 1 is napping for 1581ms
age=7130, helper 3 is napping for 1279ms
age=9490, helper 2 is napping for 358ms
age=9850, helper 2 is napping for 1079ms
age=8410, helper 3 is napping for 1522ms
age=12540, helper 1 is napping for 119ms
age=12660, helper 1 is napping for 1899ms
age=10930, helper 2 is napping for 238ms
age=11170, helper 2 is napping for 483ms
age=9940, helper 3 is napping for 1017ms
age=11660, helper 2 is napping for 1924ms
must stop now
% ./multiple_machines 3 2 10 king queen tweedle
resource user starting, 3 helpers, 2 napping time, 10 running time
Virtual machine starting up on machine king
Virtual machine starting up on machine queen
Cannot create vm on tweedle so aborting
                                              */