Overview of LU 6.2 transaction processing

Although each LU 6.2 application program is unique, part of the initial sequence of information is similar from one application program to another. The following examples show a typical sequence for an inquiry transaction for both the initiator and the responder.

Initiator's view of the inquiry transaction:

At Application Startup
- APPC=YES on the APPL statement.
- Open ACB.
- Enable sessions—SETLOGON OPTCD=START.
- Initialize session limits with CNOS—APPCCMD.
Ongoing:
- Allocate a conversation—APPCCMD.
- Send data—APPCCMD.
- Receive and wait for a reply—APPCCMD.
- Deallocate the conversation—APPCCMD.

Responder's view of the inquiry transaction:

At Application Startup:
- APPC=YES on the APPL statement.
- Open ACB.
- Enable sessions—SETLOGON OPTCD=START.
- Be informed of session limits—ATTN (CNOS) exit.
Ongoing:
- Be informed of the allocate—ATTN (FMH-5) exit or RPL.
- Receive the allocate—APPCCMD.
- Receive the data—APPCCMD.
- Send the reply—APPCCMD.
- Receive deallocate—APPCCMD.
- Wait for the next request.