[GHC] #7839: After forkIO'ing on Intel Mac, putStrLn (presumably) reports "hPutChar: failed (Operation not supported)"

[GHC]

#7839: After forkIO'ing on Intel Mac, putStrLn (presumably) reports "hPutChar:
failed (Operation not supported)"
----------------------------------------+-----------------------------------
Reporter:  thorkilnaur                  |          Owner:                
    Type:  bug                          |         Status:  new           
Priority:  normal                       |      Component:  Runtime System
 Version:  7.7                          |       Keywords:                
      Os:  MacOS X                      |   Architecture:  x86           
 Failure:  Incorrect result at runtime  |      Blockedby:                
Blocking:                               |        Related:                
----------------------------------------+-----------------------------------
 Investigating #7715 on the tn23 builder, which is
 {{{
 $ uname -a
 Darwin thorkil-naurs-intel-mac-mini.local 9.8.0 Darwin Kernel Version
 9.8.0: Wed Jul 15 16:55:01 PDT 2009; root:xnu-1228.15.4~1/RELEASE_I386
 i386
 $
 }}}
 I ran into:
 {{{
 $ cat T7715O.hs
 import Control.Monad
 import Control.Concurrent
 import System.IO
 import System.Environment

 main' c d2 = do
     replicateM_ c $ forkIO $ do
         putStrLn "Hello, world!"
     threadDelay d2

 mainArgsInterpret [cS,d2S] = main' (read cS) (read d2S)

 main :: IO ()
 main
   = do
       hSetBuffering stdout NoBuffering
       hSetBuffering stderr NoBuffering
       args <- getArgs
       mainArgsInterpret args
 $
 /Users/thorkilnaur/tn/builders/GHCBuilder/tn23/builder/tempbuild/build/inplace/bin
 /ghc-stage2 --make T7715O.hs -threaded -debug -rtsopts
 [1 of 1] Compiling Main             ( T7715O.hs, T7715O.o )
 Linking T7715O ...
 $ ./T7715O 25 10000000
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 Hello, world!
 HeT7715O: <stdout>: hPutChar: failed (Operation not supported)
 T7715O: <stdout>: hPutChar: failed (Operation not supported)
 $
 }}}
 This doesn't happen on
 {{{
 $ uname -a
 Linux tn24 3.2.0-39-generic #62-Ubuntu SMP Wed Feb 27 22:05:17 UTC 2013
 i686 i686 i386 GNU/Linux
 $
 }}}
 Best regards
 Thorkil

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/7839>
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