Hi! Im porting my HsShellScript library to GHC-7.0.4 and to Cabal/Hackage. It builds and installs fine: ~/src/hsshellscript-3.0.0 $ cabal clean cleaning... ~/src/hsshellscript-3.0.0 $ cabal configure Resolving dependencies... Configuring hsshellscript-3.0.0... ~/src/hsshellscript-3.0.0 $ cabal build Preprocessing library hsshellscript-3.0.0... Building hsshellscript-3.0.0... (...) Registering hsshellscript-3.0.0... ~/src/hsshellscript-3.0.0 $ cabal haddock Running Haddock for hsshellscript-3.0.0... Preprocessing library hsshellscript-3.0.0... (...) Documentation created: dist/doc/html/hsshellscript/index.html ~/src/hsshellscript-3.0.0 $ cabal install Resolving dependencies... Configuring hsshellscript-3.0.0... Preprocessing library hsshellscript-3.0.0... Building hsshellscript-3.0.0... Registering hsshellscript-3.0.0... Installing library in /home/v/.cabal/lib/hsshellscript-3.0.0/ghc-7.0.4 Registering hsshellscript-3.0.0... I've made a fine little test program src/test.hs: import HsShellScript main = (outm "3\n1\n2\n") -|- exec "/usr/bin/sort" ["-n"] But this doesn't work. It generates a mysterious error message: ~/src/hsshellscript-3.0.0 $ src/test test: <stderr>: hPutStr: illegal operation (handle is closed) test: timer_settime: Invalid argument "timer_settime" occurs only in the generated test binary. It doesn't occur anywhere in the library or in "/usr/bin/sort": ~/src/hsshellscript-3.0.0 $ find -type f -print0|xargs -0 egrep timer_settime Übereinstimmungen in Binärdatei ./src/test. ~/src/hsshellscript-3.0.0 $ egrep timer_settime /usr/bin/sort (no output) It looks like GHC has introduced this mysterous call of timer_settime. What does that mean? Thanks for any help, Volker W.