Are Thread Input queues global?

Question

In win32, are thread input queues global to all applications? So Application A can attach itself to application B's thread input queue?

Answer 1

AttachThreadInput will do it in fact. A thread in application A can attach itself to the message queue owned by a thread in application B, IF the two processes exist on the same desktop AND process B is not at a higher integrity level .

Answer 2

There's an API that will let you merge your spyware's input queue with the user's banking application. This kind of thing is gradually getting closed down.