Verbs and Built-in Functions › &APPC PREPARE_TO_RECEIVE

&APPC PREPARE_TO_RECEIVE

&APPC PREPARE_TO_RECEIVE changes processing from sending to receiving data.

PREPARE_TO_RECEIVE indicates that the conversation has terminated send operations and is next expecting to receive data.

This verb has the following format:

&APPC { PREPARE_TO_RECEIVE | PREPARE }
      [ TYPE={ SYNC | FLUSH | CONFIRM }  ]
      [ ID=id ]

Operands:

TYPE={ SYNC | FLUSH | CONFIRM }

Specifies the level of confirmation required for any data previously sent to the remote conversation partner as follows:

• TYPE=SYNC is the default and, if the conversation sync level is CONFIRM, then it is equivalent to the PREPARE_TO_RECEIVE TYPE=CONFIRM option; otherwise a PREPARE_TO_RECEIVE TYPE=FLUSH is assumed.
• TYPE=FLUSH results in all data being flushed, forcing its transmission to the conversation partner, but no confirmation reply is required (see Notes for this option).
• TYPE=CONFIRM results in all data being flushed and a confirmation being requested (see Notes for this option).

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.

Examples: &APPC PREPARE_TO_RECEIVE

&APPC PREPARE_TO_RECEIVE TYPE=FLUSH

&APPC PREPARE_TO_RECEIVE TYPE=CONFIRM

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 PREPARE_TO_RECEIVE request is issued from send state only, and results in receive state being entered.

Notes:

• In many cases the use of PREPARE_TO_RECEIVE is eliminated without loss of function. Since it implies that the next action on the conversation is to receive data, the eventual receipt of such data from the remote conversation partner is interpreted as implicit confirmation of any previous data sent, thus eliminating the need for the remote program to issue an explicit CONFIRMED request before sending its data.
• Further, if the next action locally is to receive, the PREPARE_TO_RECEIVE (TYPE=FLUSH) request itself is implied by simply issuing a RECEIVE request following the completion of all SEND requests.

Relationship to LU6.2 Verb Set:

&APPC PREPARE_TO_RECEIVE is equivalent to the LU6.2 verb MC_PREPARE_TO_RECEIVE. The LU6.2 verb has a LOCKS parameter which is not supported by &APPC.

More information:

&APPC Return Code Information

&RETCODE and &ZFDBK