diff --git a/preditor/stream/director.py b/preditor/stream/director.py
index ded2338f..87206703 100644
--- a/preditor/stream/director.py
+++ b/preditor/stream/director.py
@@ -32,9 +32,11 @@ def __init__(self, manager, state, old_stream=None, *args, **kwargs):
             old_stream = None
         elif old_stream is None:
             if state == STDOUT:
-                old_stream = sys.stdout
+                if getattr(sys.stdout, 'name', '') != 'nul':
+                    old_stream = sys.stdout
             elif state == STDERR:
-                old_stream = sys.stderr
+                if getattr(sys.stderr, 'name', '') != 'nul':
+                    old_stream = sys.stderr
         self.old_stream = old_stream
 
     def close(self):