default-application-window-subkey

Arguments:

Returns the default value for the subkey argument of the functions add-application-window, find-application-window, and remove-application-window. It is probably not useful for an application to call this function directly. It is also sufficiently obscure that you likely need not concern yourself with it.

On platforms where Allegro's threads are native operating system threads (in which case the value of *use-single-cg-event-handling-process* is nil), this function returns the current process. On non-native thread platforms, this function returns the keyword :global.

The idea behind the subkey argument to add-application-window was to allow windows in distinct processes to have the same name, and still allow find-application-window to find the correct window when called in event-handler callback code of windows in the same process. This works because event callback code runs in the creation-process of each window. But on non-native threads platforms, this does not work out because there is only a single event queue for the single operating system thread, and so the events for windows created in all Lisp processes are handled in a single event-handling process. So the subkey is effectively not used by default on these platforms.

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This page was not revised from the 8.1 page.
Created 2010.1.21.