ISSUE ERROR in response to ISSUE PREPARE

In an APPC mapped conversation, a transaction issues a SYNCPOINT command and its partner responds with a SYNCPOINT command.

Figure 1 illustrates an ISSUE ERROR command being used in response to ISSUE PREPARE on an APPC mapped conversation. The figure also shows the conversation state before each command and the state and EIB fields set after each command. You can also send ISSUE ERROR before receiving ISSUE PREPARE; but this is not shown, because the results are the same.
Figure 1. ISSUE ERROR in response to ISSUE PREPARE on an APPC mapped conversation.
In this figure, transaction A is communicating with transaction B using an APPC mapped conversation. Initially, transaction A's conversation with B is in send state , and transaction B's conversation with A is in receive state .
  1. Transaction A issues an ISSUE PREPARE command; the syncpoint request is transmitted, and the transaction is suspended until a response is received from transaction B.
  2. Transaction B issues a RECEIVE command which returns control immediately; EIBSYNC and EIBRECV are set, and its conversation is in syncreceive state .
  3. Transaction B issues an ISSUE ERROR command; its conversation is in send state .
  4. Transaction B issues a WAIT command; the error indication is transmitted to transaction A; transaction B's conversation is in send state .
  5. Transaction A's ISSUE PREPARE command completes; EIBERR is set; transaction A's conversation is in receive state .
This figure shows the state changes, and the EIB flags that are set, when an ISSUE ERROR command is issued in response to an ISSUE PREPARE command on an APPC mapped conversation.