OCaml - Compile OCaml and C code that uses Ctypes -

i'm trying learn how call routines in c directly ocaml code, using ctypes library.

i have basic example 2 files: hello.ml , hello.c.

hello.ml looks this:

open ctypes open foreign  let hello =      foreign "hello" (float @ -> returning void) ;;  let () =      hello 3.15 ;;

hello.c looks this:

#include <stdio.h>  void hello(double x) {     if ( x > 0)         printf("hello!\n"); }

how compile these 2 files 1 executable?

the process of manually compiling/linking code scary me , don't understand well. use makefile template compile code because that's easy.

here's example use on os x.

in simple.c

int adder(int a, int b) {     return + b; }

and in simple.ml

open ctypes open foreign let adder_ = foreign     "adder" (int @-> int @-> returning int)  let () =   print_endline (string_of_int (adder_ 1 2))

then

clang -shared simple.c -o simple.so  ocamlfind ocamlopt -package ctypes.foreign -cclib simple.so -linkpkg simple.ml -o test ./test

and should print out 3 on terminal.

harsh