General Change Notification: 3.3 System Notification: Removal from a System List

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You should use GCNListRemove() to remove an object from a system GCN list. You must pass the notification ID ( GCNStandardListType and Manufacturer ID) and the optr of the object to be removed. The optr of the object in question will only be removed from the list of the particular change specified. If the optr is on several GCN lists, those other lists will remain unchanged.

An object or process in the course of dying must remove itself from all GCN lists that it is currently on. You should therefore keep track of all GCN lists you add a particular object to. It is usually convenient for a process to remove itself from these lists within its MSG_GEN_PROCESS_CLOSE_APPLICATION message handler or for an object to remove itself in its MSG_META_DETACH handler.

Code Display 9-2 Removing a Process from a GCN list

@method MyProcessClass, MSG_GEN_PROCESS_CLOSE_APPLICATION {
	optr 		myThread;
	myThread = ConstructOptr(GeodeGetProcessHandle(), NullChunk);
	GCNListRemove(myThread, MANUFACTURER_ID_GEOWORKS, GCNSLT_FILE_CHANGE);
	@callsuper;
}
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