Receiving Data

Use a basic conversation when you need to receive more than one logical record in one buffer. This option can improve your program's execution efficiency by enabling it to receive several logical records with one request (the BUFFER option).

When you use this basic conversation feature, LU 6.2 places the logical records in your buffer with the 2-byte LL fields intact. The bytes are reversed from normal IBM-compatible PC order.

Your program must examine the returned fields of the verb to determine if it has received a complete logical record and, if so, where the next logical record begins. LU 6.2 provides the rest of an incomplete logical record after a subsequent request to receive data.

If you want to receive one higher/user level record with a single request, use a mapped conversation. As you receive data with the mapped conversation verbs, LU 6.2 ends the receive operation when your program receives a complete higher/user level record or when your buffer is full. LU 6.2 supplies a return code when it fills your buffer before your program has received a complete logical record.

Your program can receive the rest of the higher/user level record by issuing a subsequent request to receive data. The LU 6.2 mapped conversation support removes any length fields and automatically concatenates logical records as necessary.