By using the native API, you assert that you know what you're doing and how to fix problems caused by using it. If you don't, you shouldn't be using it.
Before the inclusion of glfw3native.h, you must define exactly one window API macro and exactly one context API macro. Failure to do this will cause a compile-time error.
The available window API macros are:
GLFW_EXPOSE_NATIVE_WIN32 
GLFW_EXPOSE_NATIVE_COCOA 
GLFW_EXPOSE_NATIVE_X11 
The available context API macros are:
GLFW_EXPOSE_NATIVE_WGL 
GLFW_EXPOSE_NATIVE_NSGL 
GLFW_EXPOSE_NATIVE_GLX 
GLFW_EXPOSE_NATIVE_EGL 
These macros select which of the native access functions that are declared and which platform-specific headers to include. It is then up your (by definition platform-specific) code to handle which of these should be defined. 
- Returns
 - The 
NSWindow of the specified window.  
 
 
      
        
          | EGLContext glfwGetEGLContext  | 
          ( | 
          GLFWwindow *  | 
          window | ) | 
           | 
        
      
 
- Returns
 - The 
EGLContext of the specified window.  
 
 
      
        
          | EGLDisplay glfwGetEGLDisplay  | 
          ( | 
          void  | 
           | ) | 
           | 
        
      
 
- Returns
 - The 
EGLDisplay used by GLFW.  
 
 
      
        
          | EGLSurface glfwGetEGLSurface  | 
          ( | 
          GLFWwindow *  | 
          window | ) | 
           | 
        
      
 
- Returns
 - The 
EGLSurface of the specified window.  
 
 
      
        
          | GLXContext glfwGetGLXContext  | 
          ( | 
          GLFWwindow *  | 
          window | ) | 
           | 
        
      
 
- Returns
 - The 
GLXContext of the specified window.  
 
 
- Returns
 - The 
NSOpenGLContext of the specified window.  
 
 
- Returns
 - The 
HGLRC of the specified window.  
 
 
- Returns
 - The 
HWND of the specified window.  
 
 
      
        
          | Display* glfwGetX11Display  | 
          ( | 
          void  | 
           | ) | 
           | 
        
      
 
- Returns
 - The 
Display used by GLFW.  
 
 
- Returns
 - The 
Window of the specified window.