Now can run the demux nodelet with ros/nodelet_core#80 , but it isn't…

… doing what I'd like it to (split the messages between two topics). Also nodelet_demo crashes, need to debug that

nodelet_demo/launch/demo.launch

@@ -4,6 +4,7 @@
   <arg name="mt_callback" default="false" />
   <arg name="use_demux" default="false" />
   <arg name="use_input2" default="false" />
+  <arg name="load_nodelet" default="true" />
 
   <group>
     <node pkg="nodelet" type="nodelet" name="manager" args="manager"
@@ -13,7 +14,8 @@
 
     <group if="$(arg use_demux)" >
       <node name="gen_input" pkg="nodelet_demo" type="gen_input.py"
-          output="screen" if="false" >
+          output="screen"
+          ns="data_demux" >
         <param name="period" value="$(arg period)" />
         <remap from="input" to="input" />
       </node>
@@ -28,19 +30,21 @@ nodelet: /usr/include/boost/smart_ptr/shared_ptr.hpp:641: typename boost::detail
 [manager-1] process has died [pid 10468, exit code -6, cmd /opt/ros/kinetic/lib/nodelet/nodelet manager __name:=manager __log:=/home/lucasw/.ros/log/6f210a04-927b-11e8-9cee-d8fc93bc28de/manager-1.log].
 
 The pcl demux also fails, but doesn't give the assertion failure.
+
+It's odd that demux uses private namespaces for the inputs and outputs
       -->
       <!-- args="load pcl/NodeletDEMUX manager" output="screen"-->
       <node pkg="nodelet" type="nodelet" name="data_demux"
           args="load Float32NodeletDemux manager"
           output="screen">
-        <!--remap from="input" to="input" /-->
+        <!--remap from="input" to="/input" / -->
         <rosparam>
-          output_topics: [input1, input2]
+          output_topics: [/input1, /input2]
         </rosparam>
       </node>
     </group>
 
-    <group unless="$(arg use_demux)">
+    <group unless="$(arg use_demux)" >
       <node name="gen_input1" pkg="nodelet_demo" type="gen_input.py"
           output="screen" >
         <param name="period" value="$(arg period)" />
@@ -56,11 +60,14 @@ The pcl demux also fails, but doesn't give the assertion failure.
     </group>
 
     <!-- to debug this don't run the load here, instead just run the manager
-      and attach to it with gdb -p process_num and then run the load to
+      and attach to it with
+          gdb -p process_num -ex cont
+      and then run the load to
       see how it may be immediately crashing -->
     <node pkg="nodelet" type="nodelet"
         name="demo0"
         args="load nodelet_demo/NodeletDemo manager"
+        if="$(arg load_nodelet)"
         output="screen">
       <param name="callback_delay" value="1.0" />
       <param name="mt_callback" value="$(arg mt_callback)" />