basvandijk authored Feb 07, 2012 and Simon Marlow committed Feb 08, 2012

Fixed asynchronous exception bugs in readProcess and readProcessWithExitCode This patch fixes the following two bugs:

1) If an asynchronous exception was thrown to the thread executing
   readProcess somewhere after createProcess was executed, the standard handles
   would not be closed anymore resulting in a "handle leak" so to speak.

   This is fixed by catching exceptions in the IO processing code and
   closing the standard handles when an exception occurs.
   Additionally, I also terminate the process and wait for its termination.

2) If an asynchronous exception was thrown to the
   stdout/stderr-read-thread it did not execute the putMVar anymore
   resulting in a dead-lock when takeMVar was executed.

   This is fixed by properly catching exception in the read-thread
   and propagating them to the parent thread which will then handle
   them as described above.