| GetWindowThreadProcessId The GetWindowThreadProcessId function retrieves the identifier of the thread that created the specified window and, optionally, the identifier of the process that created the window. | VB4-32,5,6 Declare Function GetWindowThreadProcessId Lib "user32" Alias "GetWindowThreadProcessId" (ByVal hwnd As Long, lpdwProcessId As Long) As Long
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 | Operating Systems Supported | 
 | Requires Windows NT 3.1 or later; Requires Windows 95 or later | 
 
 | · hWnd Identifies the window.
 
 · lpdwProcessId
 Points to a 32-bit value that receives the process identifier. If this parameter is not NULL, GetWindowThreadProcessId copies the identifier of the process to the 32-bit value; otherwise, it does not.
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 | The return value is the identifier of the thread that created the window. | 
 
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