def findpid(pid_or_file)
  if ::File.file?(pid_or_file)
    if ::File.readable?(pid_or_file)
      pid = ::File.read(pid_or_file).to_i
    else
      Chef::Log.error("File #{pid_or_file} isn't readable")
    end
  else
    pid = pid_or_file.to_i
  end
  # Test if pid exist
  begin
    Process.getpgid(pid)
  rescue Errno::ESRCH
    Chef::Log.error("Pid #{pid} not found")
  end
  pid
end
