BufferMode not preserved when handle goes through silence/capture

[mitchellwrosen]

This is probably a rare use case, but maybe one you didn't consider. I have a commandline app that sets stdout to NoBuffering in main. If I launch an external process and wish to silence it, I have to reset the BufferMode. Here's my workaround:

hSilence' :: [Handle] -> IO a -> IO a
hSilence' hs action = do
    bs <- mapM hGetBuffering hs
    result <- hSilence hs action
    mapM_ (\(h,b) -> hSetBuffering h b) (zip hs bs)
    return result

[hesselink]

Thanks for reporting this! I just ran into this issue as well, but with stderr, which is not buffered by default. It actually caused a deadlock in my app somehow, I think.

[soenkehahn]

Fixed and released to hackage as 1.2.5.