Re: [Haskell-cafe] FFI Newbie: c functions that want pointers to objects

2008-10-16 Thread Creighton Hogg
On Thu, Oct 16, 2008 at 7:28 AM, Mauricio <[EMAIL PROTECTED]> wrote: > Hi, > > Some functions in C changes data using pointers, > like this example: > > void change_int (int *n) > { > *n ++; > } > > What is the proper way to handle that? I > guess I should wrap it like this: > > foreign ccall "cha

[Haskell-cafe] FFI Newbie: c functions that want pointers to objects

2008-10-16 Thread Mauricio
Hi, Some functions in C changes data using pointers, like this example: void change_int (int *n) { *n ++; } What is the proper way to handle that? I guess I should wrap it like this: foreign ccall "change_int" change_int :: Ptr CInt -> IO () Can I use that on a CInt in Haskell code? Like t