Prototype two workers: blocking and multiplexing

lib/uh/wm/workers/mux.rb

@@ -0,0 +1,18 @@
+module Uh
+  module WM
+    module Workers
+      class Mux < Base
+        def initialize timeout: 1
+          super
+          @timeout = timeout
+        end
+
+        def work_events
+          @before_wait.call if @before_wait
+          if res = select(@ios, [], [], @timeout) then @on_read.call res
+          else @on_timeout.call if @on_timeout end
+        end
+      end
+    end
+  end
+end