Sending logical record data

Logical record data is usually of interest only to the transaction programs. It could, for example, consist of a bank balance inquiry and reply.

Logical record data is sent and the SEND buffer is flushed with the following APPCCMD macroinstructions:

APPCCMD CONTROL=SEND, QUALIFY=DATACON
APPCCMD CONTROL=SEND, QUALIFY=DATAFLU
APPCCMD CONTROL=SENDRCV, QUALIFY=DATAFLU
APPCCMD CONTROL=DEALLOC, QUALIFY=DATACON
APPCCMD CONTROL=DEALLOC, QUALIFY=DATAFLU
APPCCMD CONTROL=PREPRCV, QUALIFY=DATACON
APPCCMD CONTROL=PREPRCV, QUALIFY=DATAFLU

The SEND buffer is also flushed with the following APPCCMD macroinstructions:

APPCCMD CONTROL=SEND, QUALIFY=FLUSH
APPCCMD CONTROL=DEALLOC, QUALIFY=CONFIRM
APPCCMD CONTROL=DEALLOC, QUALIFY=FLUSH
APPCCMD CONTROL=PREPRCV, QUALIFY=CONFIRM
APPCCMD CONTROL=PREPRCV, QUALIFY=FLUSH

The DATAFLU and DATACON macroinstructions provide new data and, additionally, flush the SEND buffer. The DATACON macroinstruction also sends a confirmation request. The FLUSH macroinstruction does not provide new data to VTAM® but causes VTAM to send buffered data to the partner LU.

When sending data, the application program sets the AREA field of the RPL to point to the conversation data and the RECLEN field to the length of the data being sent. (See Buffer list requirements for details on using buffer lists to send data.)