Verbs and Built-in Functions › &APPC RECEIVE_NOTIFY

&APPC RECEIVE_NOTIFY

&APPC RECEIVE_NOTIFY requests that a notification be sent to the procedure when data is available to be received (for example, by a RECEIVE_IMMEDIATE request).

RECEIVE_NOTIFY indicates this is an asynchronous conversation receive request. If the request is accepted, the procedure continues execution and is notified of data arrival, or other completion condition, by a notification event being queued to the procedure's internal environment (see below for more details on the form of notification). No data is ever returned by this request. When the notify event is received, the RECEIVE_IMMEDIATE or RECEIVE_AND_WAIT requests is used to return any data that arrived.

This verb has the following format:

&APPC RECEIVE_NOTIFY 
    [ ID={ ANY | CLIENTS | SERVERS | id } ]

Operand:

ID={ ANY | CLIENTS | SERVERS | id }

If ID=ANY is specified, no state changes occur, but the receive request is satisfied by any conversation, either client or server, that is in receive state.

If ID=CLIENTS is specified, no state changes occur, but the receive request is satisfied by any client conversation that is in receive state. If operating in automatic connection accept mode, a new conversation can provide the data that satisfies such a receive.

If ID=SERVERS is specified, no state changes occur, but the receive request is satisfied by any server conversation that is in the receive state.

ID=id Specifies the conversation identifier (as first returned by the system variable &ZAPPCID after successful allocation) that references a particular conversation. If this parameter is omitted, the current (last referenced, or only) conversation is assumed.

Example: &APPC RECEIVE_NOTIFY

&APPC RECEIVE_NOTIFY

Return Codes:

The return codes are as follows:

0

Request successful

4

Request unsuccessful

8

Remote program error

12

State check

16

Request or conversation error

&ZFDBK is also set, plus all APPC system variables.

State Transition:

The RECEIVE_NOTIFY request is issued from either send or receive state and the conversation enters receive state while the WHAT_RECEIVED indicator (&ZAPPCWR) contains DATA (that is, DATA_COMPLETE, DATA_TRUNCATED or DATA_INCOMPLETE).

If the WHAT_RECEIVED indicator contains SEND (where the remote conversation partner has issued PREPARE_TO_RECEIVE) the local state changes to send.

If the WHAT_RECEIVED indicator contains CONFIRM, CONFIRM_SEND, or CONFIRM_DEALLOCATE then the local procedure should issue the CONFIRMED request following which the state changes to receive, send, or deallocate respectively.

Notification Message Format:

When a RECEIVE_NOTIFY request is satisfied, either successfully or unsuccessfully, the following message is placed on the request queue of the internal environment for the NCL procedure:

N00101 NOTIFY: APPC EVENT: RECEIVE RESOURCE: &zappcid

where the value &zappcid is the conversation identifier returned by the original ALLOCATE request, or set when this procedure was attached as the remote end of the conversation.

Notes:

• When RECEIVE_NOTIFY is issued from send state, an implied PREPARE_TO_RECEIVE TYPE=FLUSH is issued. This is the most efficient way of changing the direction of conversation flow.
• If the remote conversation partner deallocates the conversation normally, the &RETCODE is set to 4, and &ZFDBK to 4.

Relationship to LU6.2 Verb Set:

&APPC RECEIVE_NOTIFY is equivalent to the LU6.2 verb MC_POST_ON_RECEIPT.

More information:

&APPC Return Code Information

&RETCODE and &ZFDBK