Waiting for other spawned process with timeout

waiting_for_process.rb

require 'timeout'
require 'shellwords'

cmd = "foo"
out = "bar.out"
cmd = "#{cmd} -o #{Shellwords.escape(out)}"

timeout = 1 

# puts cmd 

pid = spawn(cmd, :pgroup => true, :in=>"/dev/null", :out => "/dev/null", :err => "/dev/null")
process = Process.detach(pid)

begin
  Timeout.timeout(timeout) do
    process.join
  end 
rescue Timeout::Error
  Process.kill :TERM, -pid
end

if process.value.exitstatus > 0 
  # error trap
end