# File lib/resque/scheduler/signal_handling.rb, line 15
      def register_signal_handlers
        (Signal.list.keys & %w(INT TERM USR1 USR2 QUIT)).each do |sig|
          trap(sig) do
            signal_queue << sig
            # break sleep in the primary scheduler thread, alowing
            # the signal queue to get processed as soon as possible.
            @th.wakeup if @th && @th.alive?
          end
        end
      end