HOWTO use ocamlsdl with the Mingw port of OCaml and the Cygwin environment


1. Get Cygwin/Mingw. Get the development packages, namely gcc and gcc-mingw.
   I couldn't get gcc 3.2 to work so I used the package gcc-2.
   
2. Get OCaml 3.06 from INRIA and build it. Instructions are in the file README.win32.
   Follow the instructions for "Mingw port" (smthg like that). The "make opt.opt" step
   kept crashing my Windows so I skipped it. 
   Install ocaml somewhere.
   
3. Get SDL, compile and install. There are some additional instructions here :
   http://www.libsdl.org/extras/win32/gcc.html like where to get nasm.exe.
   
4. Now get and unpack ocamlsdl-0.6.1

5. Make sure the ocaml compilers are in your PATH (try ocamlc -v).
   Make sure sdl-config is in your PATH.
   Make sure the SDL.dll is in your PATH.
   Run ./configure -- it should work ; if not, check what's wrong in config.log .
   make -- builds the libraries (no toplevel).
   cd samples && make testalpha.test testalpha.opt  -- try to run them, they should work.

   
What it does:

 The file mlsdl_main.c is a near copy of SDL_main.c. It defines a WinMain entry point
 that overrides the usual entry point of the caml program. It does a few initialisation
 stuff and then calls "caml_main" to start the caml program (whereas the SDL_main.c supplied
 by SDL calls a regular C "main" entry point). This mlsdl_main.c file is compiled as a 
 liblsdl_main.a library and -lmlsdl_main is added to the link options of sdl.cma 
 (in replacement of -lSDL_main).
 
   
   
   
Some various gotchas:
  - this produces windowed apps, not console apps, so they will not pop up a console 
    when starting. OTOH, there's no standard or error output. In particular, 
    uncaught exceptions do not produce an error message.
    
  - ocaml compilers do not like cygwin-style paths. You can use the cygpath tool to convert them.
    Instead of :
       -I ~/ocamlsdl-0.6/src
    try :
       -I $(cygpath -w ~/ocamlsdl-0.6/src)


-- 
	Olivier Andrieu <oliv__a@users.sourceforge.net>