Hello
Lets say I have a library in C with a header like this:
#include
/*really big structure*/
typedef struct {
int *a;
int *b;
/*lots of stuff
...
*/
int *z;
} foo;
/*this function allocate memory and fill the structure, reading from a
file*/
int create_foo(foo *f,FILE *file,int x,int y);
/*some functions that use the structure*/
int use_foo(foo *f,int w);
/*a funtion that releases the memory*/
int destroy_foo(foo *f);
And I want to use it in haskell using FFI. I can create a .hsc file like
this:
{-# LANGUAGE CPP, ForeignFunctionInterface #-}
import Foreign
import Foreign.C.Types
#include "foo.h"
newtype Foo = Foo ()
foreign import ccall "static foo.h create_foo"
c_create_foo :: Ptr (Foo) -> Ptr (CFile) -> CInt -> CInt -> IO CInt
foreign import ccall "static foo.h use_foo"
c_use_foo :: Ptr (Foo) -> CInt -> IO CInt
foreign import ccall "static foo.h destroy_foo"
c_destroy_foo :: Ptr (Foo) -> IO CInt
It compiles but I have no idea how to call c_create_foo and get back Foo
Any suggestions?
thanks
