XCF does not require that the target member be the member that responds to a message. Any member of the XCF group can use the response identifier to respond to the message. However, XCF expects the original target member to be the one to respond. If that target member becomes inactive, XCF no longer expects a response from that member. When no further responses are expected, XCF considers the message to be complete. Any response that arrives after the message completes is discarded.

If your application protocol has some other member send a response on behalf of the original target member, you must be aware that XCF has no ability to recognize this situation. If the original target member becomes inactive, the timing could be such that the message will complete (because XCF no longer expects the response) before the other member's response arrives. The message notify user routine would be missing a response even though the member that your application expects to respond is active and still has plenty of time remaining before the message times out.