diff --git a/pdfminer/high_level.py b/pdfminer/high_level.py
index b79a1c0..bd79158 100644
--- a/pdfminer/high_level.py
+++ b/pdfminer/high_level.py
@@ -82,3 +82,4 @@ def extract_text_to_fp(inf, outfp,
         page.rotate = (page.rotate + rotation) % 360
         interpreter.process_page(page)    
 
+    device.close()