DRx responses

In all cases except those mentioned in the next paragraph, FEPI automatically gives a positive DRx response when the inbound data indicates that a response is required. This response flows on the next FEPI command (SEND, RECEIVE, CONVERSE, FREE, or START).

The automatic response is not issued if the next command for a conversation is a FEPI ISSUE CONTROL or a FEPI FREE PASS. Thus, if you want to send your own response, perhaps for added certainty or confirmation of particularly sensitive changes, you would do so using FEPI ISSUE CONTROL. The response type that is required can be determined from the RESPSTATUS option of FEPI RECEIVE and FEPI CONVERSE.

You can send your own responses with either formatted data or data stream. But do not use the following because they can cause FEPI to send responses automatically:

Key stroke formatted data containing an attention key that is not the final key stroke
FEPI CONVERSE with the POOL option to use a temporary conversation.

If you respond negatively a back-end CICS® system will discard the data but an IMS system will resend it.