Ok, in summary I see the following possibilities for the return value of

#7229: Detecting if a process was killed by a signal is impossible --------------------------------------+------------------------------------ Reporter: benmachine | Owner: Type: bug | Status: new Priority: high | Milestone: 7.8.1 Component: libraries/process | Version: Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: Unknown/Multiple Type of failure: None/Unknown | Difficulty: Unknown Test Case: | Blocked By: Blocking: | Related Tickets: --------------------------------------+------------------------------------ Comment (by hvr): Replying to [comment:18 hvr]: the existing `waitForProcess` call on POSIX systems:

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5. PS/Just for the record: it would also be possible (since `WIFEXITED(s)` and `WIFSIGNALED(s)` are mutually exclusive) to encode signals as negative integers -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/7229#comment:28 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler