Some processing considerations

Any of the EXEC CICS commands (except EXEC CICS RECEIVE—see Modifying the initial terminal data) can be issued from the routing program. You are likely to find the EXEC CICS® INQUIRE CONNECTION and INQUIRE IRC commands particularly useful if you want to confirm that a link is available before routing a transaction. The EXEC CICS INQUIRE and SET commands are described in System commands.
Although the routing program can issue any EXEC CICS command, you should consider carefully the effect of commands that alter protected resources, because changes to those resources may be committed or backed out inadvertently as a result of logic in the routed transaction. You should also consider carefully the effect of EXEC CICS SYNCPOINT and ABEND commands on APPC transaction routing.
If you want to keep information about how transactions are routed, it must be done in the user routing program, perhaps by writing the information to a temporary storage queue associated with this terminal.
Several transactions can form a single conversation with the user. At the start of the conversation, resources are allocated to record the state of the conversation. Because these resources are local to the system to which the first transaction in the conversation was routed, the routing program must be able to continue to route to this system until the end of the conversation.
It is important to avoid creating “tangled daisychains”: for any transaction that is being dynamically routed, you must avoid routing back to a node that has previously been routed from.
The dynamic routing program can be RMODE ANY but must be AMODE 31.