General Change Notification: 3 System Notification

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GCNListAdd(), GCNListSend()

The system provides several lists for common system changes which might affect your application. After signing up on one of these lists (for example, the file change list) you will be notified by the kernel whenever the specified change occurs. In most cases, all you need to do is register for notification with GCNListAdd() and intercept the kernel's notification message.

The GCN mechanism performs its functions through a common series of steps. These steps are:

  1. The object registers for notification with GCNListAdd().
  2. The change occurs.
  3. The GCN mechanism is informed of the change by the acting party (in most cases this is the system itself, although a library may also send notifications). Applications do not send notifications at the system level.
  4. The GCN mechanism dispatches notification messages to all interested parties with GCNListSend() .
  5. The object is informed of the change.
    If you need to perform some work related to this change, you should have a message handler to intercept the system messages.

Registering for System Notification

Handling System Notification

Removal from a System List

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