Creating a CICS request exit
The CICS® request exit is called by CICS Transaction Gateway in remote mode, to select a CICS server name for an ECI or ESI request. The CICS request exit can be used for request retry, dynamic server selection and for rejecting non-valid requests. If the server name returned by a CICS request exit is null, the request is sent to the default CICS server if one is specified in the configuration file (ctg.ini).
Before you begin
- The specified CICS server is no longer available (ECI_ERR_CICS_DIED or ESI_ERR_CICS_DIED).
- There are insufficient communication resources to complete the request (ECI_ERR_RESOURCE_SHORTAGE or ESI_ERR_RESOURCE_SHORTAGE).
- The specified CICS server is not available (ECI_ERR_NO_CICS or ESI_ERR_NO_CICS).
For an XA transaction, if a request is retried using a CICS request exit, the retry must use the same protocol as the original request. For example, a request that was originally attempted over EXCI cannot be retried over IPIC. If, on retry, the exit attempts to change the protocol used, the ERROR_EXIT_RETRY_INVALID return code is returned to the Client application and message CTG8468E is written to the error log.
You can pass a command to a CICS request exit dynamically using the CREXIT administration option; for more information see CICS request exit control.