When a user issues a K to sign off of TPX and all active sessions are terminated, what does TPX send to each application to inactivate the session?
Component: TPX for Z/OS
When a user issues a /I or a /K against a session, TPX issues a TERMSESS OPTCD=UNCOND (unconditional termination).
Once issued, VTAM will drive the application's Losterm exit for the session, and will send TPX an unbind at the same time to indicate that it's OK for TPX to clean up its half of the session control blocks.
This is not an error rather a normal unbind from VTAM to clean up the 'half session' with TPX.