HP-UX SNAplus2 R7 APPC Programmer's Guide

Concepts
Confirmation Processing (half-duplex)
Invoking TP Flow Invoked TP
MC_RECEIVE_AND_WAIT (primary_rc=
AP_OK)(what_rcvd =
AP_SEND)
MC_SEND_DATA
MC_CONFIRM
—>
MC_RECEIVE_AND_WAIT (primary_rc=
AP_OK)(what_rcvd =
AP_DATA_COMPLETE
)
MC_RECEIVE_AND_WAIT (primary_rc=
AP_OK)(what_rcvd =
AP_CONFIRM)
MC_CONFIRMED
<—
MC_DEALLOCATE (dealloc_type =
AP_SYNC_LEVEL)
—>
MC_RECEIVE_AND_WAIT (primary_rc =
AP_OK)(what_rcvd =
AP_CONFIRM_DEALLOCATE)
MC_CONFIRMED
<—
TP_ENDED TP_ENDED
1.3.1 Establishing the Synchronization Level
The sync_level parameter of the MC_ALLOCATE verb determines the synchronization level of the conversation.
Possible values for synchronization levels are:
•
AP_CONFIRM_SYNC_LEVEL under which the TPs can request confirmation of receipt of data and respond to such
requests
•
AP_NONE under which confirmation processing does not occur
UNIX
A third level, AP_SYNCPT (Syncpoint) can also be used, but requires additional software. For more information, see
Section 1.12, Syncpoint Support.
1.3.2 Sending a Confirmation Request
The MC_CONFIRM verb has two effects:
• To flush the local LU’s send buffer, which sends any data contained in the buffer to the partner TP
• To send a confirmation request, which the partner TP receives through the what_rcvd parameter of a receive
verb
The MC_CONFIRM verb does not complete until confirmation (or an indication that an error was detected) is
received from the partner TP.
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