class Servolux::Daemon::LogfileReader

def updated?
  s = stat
  @stat ||= s
  return false if s.nil?
  return false if @stat.mtime == s.mtime and @stat.size == s.size
  return true if @look_for.nil?
  File.open(@filename, 'r') do |fd|
    fd.seek @stat.size, IO::SEEK_SET
    while line = fd.gets
      return true if line =~ @look_for
    end
  end
  return false
ensure
  @stat = s
end