[[!comment format=mdwn
 username="joey"
 subject="""comment 5"""
 date="2016-06-22T19:24:43Z"
 content="""
Unfortunately `withFile` uses IO, instead of being generalized to MonadIO,
so the approaches that work with `withUmask` don't work with it.

One way is to write a version of withFile that's generalized to MonadIO:

	withFile' :: (MonadIO m, MonadMask m) => FilePath -> IOMode -> (Handle -> m r) -> m r
	withFile' name mode = bracket (liftIO $ openFile name mode) (liftIO . hClose)
"""]]
