"executeFile" is failing for me on Mac OS X 10.5.8, with ghc 6.12.1 when compiling with "-threaded". Compiling without -threaded, or running on linux is fine.

When compiled with -threaded, the following snippet produces the error:
testProg: /bin/echo: executeFile: failed (Operation not supported)

> import System.Posix.Process
> main = do
>
> forkProcess $ executeFile "/bin/echo" False ["Ok"] Nothing

Any suggestions for a work around for this would be appreciated.

Cheers,

--
David Powell