tighten up except - os.close only raises OSError
see bug 411881
diff --git a/Lib/popen2.py b/Lib/popen2.py
index 07ed6d6..f00cb83 100644
--- a/Lib/popen2.py
+++ b/Lib/popen2.py
@@ -62,7 +62,7 @@
         for i in range(3, MAXFD):
             try:
                 os.close(i)
-            except:
+            except OSError:
                 pass
         try:
             os.execvp(cmd[0], cmd)