Hi,

The second time I press control-c, it isn't caught -- the program exits instead.  Why?

(The context is, I'm writing an interactive program where calculations may take a long time.  Control-c during a calculation should return the user to a prompt.  As things stand, this can only be done once -- the second calculation so interrupted causes the whole program to exit.)

$ ./ctrlctest

^Cuser interrupt

^C    -- program exits!

$ cat ctrlctest.hs

module Main where

import Control.Concurrent (threadDelay)

import qualified Control.Exception as C

main :: IO ()

main = do (threadDelay 1000000 >> return ()) `C.catch` (\e -> print (e::C.AsyncException))

         main

$ ghc --version

The Glorious Glasgow Haskell Compilation System, version 7.0.3

$ uname -mrsv

Darwin 11.2.0 Darwin Kernel Version 11.2.0: Tue Aug  9 20:54:00 PDT

2011; root:xnu-1699.24.8~1/RELEASE_X86_64 x86_64