Including additional libraries

["krib@..." <krib@...>]

I have program which reads two values width and height from simple lua file:
width=200 
height=300

And it works nice if I dont include additional libraries (lua_baselibopen(L);, lua_strlibopen(L);
, etc.), but if I include them it does not work, it does not get values instead it gets some non
numeric values. Here is the code:

extern "C"
{
 #include <lua.h>
 #include <lualib.h>
 #include <lauxlib.h>
}

int width, height; /* global variables */
lua_State *L;
void load (char *filename);

int main()
{
	load("luatest.lua");
	return 0;
}

void load (char *filename) {
	L = lua_open();
//	lua_baselibopen(L);
//	lua_strlibopen(L);
//	lua_tablibopen(L);
//	lua_iolibopen(L);
//	lua_mathlibopen(L);
	if (lua_dofile(L, filename) != 0)
	{
		lua_pushstring(L,"cannot run configuration file");
		lua_error(L);
	}
	else 
	{
		lua_getglobal(L, "width");
		lua_getglobal(L, "height");
		if (!lua_isnumber(L, 1) || !lua_isnumber(L, 2))
		{
			lua_pushstring(L,"invalid values");
			lua_error(L);
		}
		else 
		{
			width = (int)lua_tonumber(L, 1);
			height = (int)lua_tonumber(L, 2);
		}
	}
	lua_close(L);
}

If I uncoment commented lines it doesnt work, if I comment them it works.

Thank you in advance.