Gary, I suggest that your point about the server needing to know immediately about a client logoff is a good argument for a system-supplied notification service, similar to ENF on z/OS.
For example, let's say that we create an *NOTIFY system service. A virtual machine, appropriately authorized is allowed to connect to the *NOTIFY service, and by sending properly constructed messages, register its desire to begin receiving, or to discontinue receiving, specific types of event notifications. Certainly, LOGON and LOGOFF notifications should be available. Other event types come to mind, such as varying a central processor online or offline, or varying a device online or offline. I feel certain that others here can recommend other event types that should be monitorable. Then, whenever an event of the requested type occurs, all registered listeners would receive the notification on the *NOTIFY path. This would at least provide a mechanism by which one of your requirements could be addressed. John P. Baker -----Original Message----- From: The IBM z/VM Operating System [mailto:[EMAIL PROTECTED] On Behalf Of Gary M. Dennis Sent: Wednesday, August 27, 2008 11:59 AM To: IBMVM@LISTSERV.UARK.EDU Subject: Re: IUCV - What's wrong with this picture? Thanks for the response on the IUCV questions. I have included below item 6 from the thread origin and a snippet from John Baker's response. Maybe I should have placed more emphasis on item 6. The server machine is going to be updating the buffer areas in all the connected client machines. Therefore, he server machine needs to know immediately when one of the guests is quiescent or logged off. IUCV will inform the server when a connection is severed. The guest machines can set in indicator in an area monitored by the server to indicate that they have begun a normal closedown *but* the "fall-off_the page" case is when a machine is logged off and the server attempts to access the buffers in a machine that no longer exists. John made a good argument for temporary IUCV connections. In that case the best way to make a determination on the active state a diagnose that issues a query command for the user in question? --. .- .-. -.-- Gary Dennis
