void callLua(lua_State* luaState, const char *func, const char *sig, ...)
{
	va_list vl;
	int narg, nres;  /* number of arguments and results */

	va_start(vl, sig);
	lua_getglobal(luaState, func);  /* get function */

	/* push arguments */
	narg = 0;
	while (*sig) {  /* push arguments */
		switch (*sig++) {
			case 'd':  /* double argument */
				lua_pushnumber(luaState, va_arg(vl, double));
				break;

			case 'i':  /* int argument */
				lua_pushnumber(luaState, va_arg(vl, int));
				break;

			case 's':  /* string argument */
				lua_pushstring(luaState, va_arg(vl, char *));
				break;
			case '>':
				sig++;
				goto endwhile;
			default:
				break;
		}
		narg++;
		debug_message("narg=%d\n", narg);
		luaL_checkstack(luaState, 1, "too many arguments");
	}
endwhile:

	/* do the call */
	nres = strlen(sig);  /* number of expected results */
	lua_pcall(luaState, narg, nres, 0);  /* do the call */

	va_end(vl);
}