thanks, but also after changing my CString/newCString to CWString/newCWString I'm getting the segfault. As I mentioned if I run the setmodulestring function from ghci everyting works fine (I get proper return value). The problem only comes if I call setmodulestring from the main.

I have simplified the main here:

main = do

let param = "FilePath"

let value = "C:/dev/misc/haskell/services/FM"

result <- liftIO $ FM.setmodulestring param value

return "done"

Another strange thing is that I can call another external function from the 'main' function without problem.

On Fri, Mar 14, 2014 at 9:52 PM, Brandon Allbery <allbery.b@gmail.com> wrote:

On Fri, Mar 14, 2014 at 4:46 PM, Miro Karpis <miroslav.karpis@gmail.com> wrote:

setmodulestring :: String -> String -> IO CInt
setmodulestring param value = do

cParam <- newCString param
cValue <- newCString value
let cParamLength = fromIntegral $ length param ::CInt

cValueLength = fromIntegral $ length value ::CInt
setVarInArray = (-1)::CInt
result <- c_setmodulestring cParam cParamLength cValue cValueLength setVarInArray

return result

The path you show earlier looks like Windows; you probably want CWString for Win32 API functions (so newCWString etc.).

--
brandon s allbery kf8nh sine nomine associates
allbery.b@gmail.com ballbery@sinenomine.net

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