Exit-list (EXLST) exit routines
These are special-purpose exit routines that VTAM® schedules when appropriate, such as on receipt of a CINIT request as a result of a logon or initiate request. The exit-routine addresses (entry points) are specified in an exit list created with the EXLST macroinstruction.
A program can define more than one exit list by using multiple EXLST macroinstructions. However, an ACB can point to only one exit list at a time.
An exit list can be specified in an ACB and thus can be used by VTAM when an exit-routine event occurs for any session with the program, including those sessions that VTAM sets up to support LU 6.2 conversations.
- The application program receives an FMH-5.
- VTAM processes a CNOS request from a partner LU or an operator command, and new session limits are established.
- The last session or each session of a mode name group is terminated.
For details on this exit routine, see Using the ATTN exit.
Not all the exit routines that application programs can supply have meaning for LU 6.2 functions. The names of the already-existing special-purpose exit routines applicable to LU 6.2 and the events that cause them to be entered are summarized in Table 1.
Exit Routine Name | Event |
---|---|
LERAD | A logic error has been detected for an RPL-based request. |
LOGON | An application program is being requested to establish a session as a primary logical unit. |
LOSTERM | A session with an application program has been terminated or disrupted, or a conditional terminate request for a session has been received. |
RELREQ | Another application program has requested a session with a logical unit that is presently in session with this program, and the logical unit is at its session limit. |
SCIP | A session-control request has been received. This exit is only scheduled for LU 6.2 sessions when a BIND request is received for the application program. The other types of session-control requests that this exit deals with are handled by VTAM for an LU 6.2 session. |
SYNAD | An error other than a logic error has been detected for an RPL-based request. |
TPEND | The VTAM operator shuts down the network or this application program, or VTAM halts or abends, or a VTAM application program is being taken over. |
- DFASY
- NSEXIT
- RESP
For more details on the special-purpose exit routines, see Using exit routines.