Response to errors

The APPCCMD macroinstruction gives the application program three major alternatives when it discovers an error. The application program can do one of the following actions:

Report it to the conversation partner
Deallocate the conversation
Deallocate the conversation and end the session supporting the conversation

The last of these is meant to be used only when a protocol error is discovered, indicating serious problems with the exchange of data over the session.

These three alternatives correspond to the following macroinstructions:

APPCCMD CONTROL=SEND, QUALIFY=ERROR
The four abnormal deallocation varieties of APPCCMD CONTROL=DEALLOC|DEALLOCQ
APPCCMD CONTROL=REJECT

APPCCMD CONTROL=DEALLOC|DEALLOCQ and APPCCMD CONTROL=SEND, QUALIFY=ERROR have additional keywords to further define the type of error to which the application program is responding. This additional level of detail helps create more understandable return codes to pass to the partner LU.

The APPCCMD CONTROL=SEND variations are:

APPCCMD CONTROL=SEND, QUALIFY=ERROR,TYPE=PROGRAM
APPCCMD CONTROL=SEND, QUALIFY=ERROR,TYPE=SERVICE
APPCCMD CONTROL=SEND, QUALIFY=ERROR,TYPE=USER

The APPCCMD CONTROL=DEALLOC variations are:

APPCCMD CONTROL=DEALLOC, QUALIFY=ABNDPROG
APPCCMD CONTROL=DEALLOC, QUALIFY=ABNDSERV
APPCCMD CONTROL=DEALLOC, QUALIFY=ABNDTIME
APPCCMD CONTROL=DEALLOC, QUALIFY=ABNDUSER

The APPCCMD CONTROL=DEALLOCQ variations are:

APPCCMD CONTROL=DEALLOCQ, QUALIFY=ABNDPROG
APPCCMD CONTROL=DEALLOCQ, QUALIFY=ABNDSERV
APPCCMD CONTROL=DEALLOCQ, QUALIFY=ABNDTIME
APPCCMD CONTROL=DEALLOCQ, QUALIFY=ABNDUSER