[Main]
Name=EV_hook
Type=Variable
Subtype=ROM Call
Header Files=events.h
Definition=EVENT_HANDLER EV_hook;

[ROM Call]
Index=$2A3

[Description]
A global variable pointing to the "hook" event handler.

[Explanation]
EV_hook is a global pointer variable which points to the "hook" event handler (or
<A HREF="$$LINK(alloc.h/NULL)">NULL</A> if there is no "hook" handler installed. Hook handler hooks
events like <A HREF="$$LINK(EV_captureEvents)">EV_captureEvents</A>, however, the application
handler (either default application handler or user handler installed with
<A HREF="$$LINK(EV_captureEvents)">EV_captureEvents</A>) is still called afterwards (see
<A HREF="$$LINK(EV_sendEvent)">EV_sendEvent</A> for more info. This is probably meant for
debugging purposes as it is never used in TIOS.
<BR><BR>
Using EV_hook you can capture all messages and process them as you like, without
overriding current handlers. So, you can use it to change behaviour of some events,
or add new functionalities. DoorsOS for example uses EV_hook to add SHIFT+ON feature.
You also can hook the APPS key and display a different menu in which your application
set will be listed (then you can start your own event driven application via
<A HREF="$$LINK(EV_captureEvents)">EV_captureEvents</A>). If you understand principles
described in this header file, this is not so hard. If you didn't understand what
is written here, don't try to play with this...

[References]
In=EV_centralDispatcher, EV_sendEventSide, homescr.h/HomeStore
