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winapi - Can a message-only window receive WM_QUERYENDSESSION?

In the debug version of the program, I create a visible window, and the WM_QUERYENDSESSION message is received by the WNDPROC. In the release version, the window is supposed to be message-only, so I specify HWND_MESSAGE as the hWndParent when calling CreateWindowEx(). Unfortunately, I then don't receive the WM_QUERYENDSESSION message anymore. Is WM_QUERYENDSESSION one of those broadcast messages mentioned here? "A message-only window [...] does not receive broadcast messages."

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MSDN gives a decent definition of a "message-only window":

A message-only window enables you to send and receive messages. It is not visible, has no z-order, cannot be enumerated, and does not receive broadcast messages. The window simply dispatches messages.

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You use them to take advantage of the message dispatch mechanism in your own code. Most typically to get a worker thread to talk to the UI thread in a thread-safe way. A message loop is the universal solution to the producer-consumer problem. Apartment marshaling in COM is implemented with a message-only window for example. Clearly such a window should be hidden and only get the messages that are defined by the app.

Don't use HWND_MESSAGE as hWndParent when calling CreateWindowEx.


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