def get_window_size(window):
    """
    Retrieves the size of the client area of the specified window.

    Wrapper for:
        void glfwGetWindowSize(GLFWwindow* window, int* width, int* height);
    """
    width_value = ctypes.c_int(0)
    width = ctypes.pointer(width_value)
    height_value = ctypes.c_int(0)
    height = ctypes.pointer(height_value)
    _glfw.glfwGetWindowSize(window, width, height)
    return width_value.value, height_value.value