ruby.rb

require 'timeout'

MAX_PROCESSES = 5
MAX_TIME = 30

command = #SOME LONG RUNNING PROCESS WITH LOTS OF OUTPUT
spoons = {}
finished_spoons = {}
unfinished_spoons = {}

MAX_PROCESSES.times do |i|
  spoon = {}
  spoon['read'], spoon['write'] = IO.pipe
  spoon['fork'] = spawn(command, :out => spoon['write'], :err => spoon['write'])
  spoons[spoon['fork']] = spoon
end

begin
  Timeout.timeout(MAX_TIME) {
    while !spoons.empty? do
      pid, status = Process.wait2
      finished_spoons[pid] = spoons[pid]
      spoons.delete(pid)
    end
  }

rescue Timeout::Error
  puts "\nNot all processes ended before timeout.  Killing remaining processes.\n"
  kill_spoons = true
end

if kill_spoons
  spoons.each do |key, spoon|
    Process.kill(9, spoon['fork'])
    unfinished_spoons[spoon['fork']] = spoon  #make it un-finished
  end
end

finished_spoons.each do |key, spoon|
  spoon['write'].close
  output = spoon['read'].read
  spoon['read'].close
  #do stuff with output
end