diff --git a/pingnet.py b/pingnet.py
index 4d381f7..4340560 100755
--- a/pingnet.py
+++ b/pingnet.py
@@ -64,10 +64,11 @@ class Pinger(threading.Thread):
                 break
 
     def ping(self, host):
-        p = subprocess.Popen(['ping', '-c', '1', '-W', '1', host],
-                             stdin=open(os.devnull),
-                             stdout=open(os.devnull, 'w'),
-                             stderr=subprocess.STDOUT)
+        with open(os.devnull, 'r+') as nul:
+            p = subprocess.Popen(['ping', '-c', '1', '-W', '1', host],
+                                 stdin=nul,
+                                 stdout=nul,
+                                 stderr=subprocess.STDOUT)
         p.wait()
         if p.returncode == 0:
             if not self.quiet: