c - Is it a mistake to check a `HWND` against `INVALID_HANDLE_VALUE`? -

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There was a small debate with me with a fellow programmer. He uses the following idiom in his code: 

  HWWWWW = some function white writers a wando (); If (hWnd! = NULL & hWnd! = INVALID_HANDLE_VALUE) {// All good} Other {// error}   
 I told him that in my opinion this is a wrong view, as There is nothing with the definition  hwnd  type  INVALID_HANDLE_VALUE , but it is certain that this is a good code, because a valid handle is never equal to  INVALID_HANDLE_VALUE Maybe  
 So, is this acceptable and correct idiom? Comparing  INVALID_HANDLE_VALUE  against 
 
  hwnd  For this it is a mistake. However, it is not a mistake in practice that will harm you.  
 Only  hwnd  is reserved as valid  CreateWindowEx  as  NULL . Now, this is an implementation description that  INVALID_HANDLE_VALUE  can not be a valid  HWND , but this is only the implementation details. The function that manages the window,  CreateWindowEx , uses  NULL  to indicate the failure  
 If you use your argument with your affiliate If you want to win, then I recommend that you look in  SomeFunctionWhichReturnsAWindow  and find out which Win32 API is called to produce  HWND . Then consult the documentation. This will show you that the  NULL  reserve has an invalid value.  
 For clarity, you must test the code against  NULL

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