Merge pull request #1985 from RubioJr9/linux_closing

Closes #1962

Author: dcwhite

src/Core/Application/Application.cc

@@ -64,9 +64,8 @@ namespace SCIRun
 {
   namespace Core
   {
-    class ApplicationPrivate
+    struct ApplicationPrivate
     {
-    public:
       CommandLineParser parser;
       boost::filesystem::path app_filepath_;
       boost::filesystem::path app_filename_;

src/Dataflow/Engine/Controller/NetworkEditorController.cc

@@ -102,6 +102,7 @@ NetworkEditorController::~NetworkEditorController()
 #ifdef BUILD_WITH_PYTHON
   NetworkEditorPythonAPI::clearImpl();
 #endif
+  executionManager_.stop();
 }
 
 namespace

src/Dataflow/Engine/Scheduler/ExecutionStrategy.cc

@@ -123,6 +123,9 @@ void ExecutionQueueManager::executeImpl(ExecutionContextHandle ctx)
 
 void ExecutionQueueManager::stop()
 {
-  executionLaunchThread_->interrupt();
-  executionLaunchThread_.reset();
-}
+  if (executionLaunchThread_)
+  {
+    executionLaunchThread_->interrupt();
+    executionLaunchThread_.reset();
+  }
+}