Re: Difference between WM_APP and WM_USER

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Hi Jeff,

I use these, but I always send my APP messages to a specific window in my
application. I agree that doing this from a DLL may be problematic. I have
seen libraries have user defined messages and mostly they just say in the
documentation that they are doing it and/or only send the messages to their
own windows which would be safe as well (or at least more safe).

Tom

"Jeff Partch [MVP]" <jeffp@xxxxxxxx> wrote in message
news:%23ukjctwhGHA.5096@xxxxxxxxxxxxxxxxxxxxxxx

The WM_APP range has always been either reserverd for future use -- before
there was a WM_APP, or reserved for use by an application for its internal
use. Because a dll is not an application it has never been appropriate for
a dll to use this message range. And again, broadcasting such a message is
outrageously irresponsible.



.

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