Hello, I have a multi-threaded and interactive application that sometimes stops responding, and it would be helpful being able to inspect the state when it doesn't. I thought the GHCi debugger could be useful here, however I see no way to signal a thread and have GHCi show me its state. Here is an example GHCi session: $ cat t.hs import Control.Concurrent import Control.Exception import Control.Monad import System.IO spawnThread :: String -> IO ThreadId spawnThread label = forkIO $ flip finally (putStrLn $ "bye " ++ label) $ forM_ [0..] $ \i -> threadDelay 1000000 $ ghci-7.10.1 t.hs -fbreak-on-exception -v0 *Main> hSetBuffering stdout LineBuffering *Main> t0 <- spawnThread "t0" *Main> throwTo t0 (ErrorCall "end") *Main> It looks like I'm not getting the "bye t0" message when stopping the thread while using -fbreak-on-exception. Is the debugger supposed to be used like this? Otherwise, is there any way in which I could inspect the state of a running thread? Thanks, Facundo