Module finalization (along the lines of calling a function on exit)

["Vijay Aswadhati" <wyseman@...>]

Searching through the archives I found this post[1] that suggests a way to call
function on exit. How does it work in practice for a module. In other words if
I have code like this:
<C code>
static int z_foo(lua_State *L);
static int z_bar(lua_State *L);
static int z_initialize();
static int z_finalize();

static const struct luaL_reg functions[] = {
  {"foo",      	z_foo},
  {"bar",      	z_bar},
  {"__gc",		z_finalize}, /* <-- does not work */
  {NULL, NULL}
};

Z_API int luaopen_z (lua_State *L) 
{
    int rac = 0, cc = z_initialize();
    if ( cc != Z_OK ) {
        z_decode_and_raise_error(L, cc, "luaopen_z");
    }
    else {
        luaL_module(L, "z", functions, 0);
        rac = 1;
    }

    return rac;
}
</C code>

Where exactly would I set the __gc hook to invoke z_finalize() function call
when the module 'z' gets unloaded. In LuaSocket and as per Diego's post there
is an "__unload" method registered as part of the base libraries, which seems
to be nothing at run time; i.e it never gets called automatically.


Help! 

-- v.a




[1] http://lua-users.org/lists/lua-l/2004-06/msg00195.html