SNAX/HLS Application Programming Manual

The Standard Verb Interface
4–2 104707 Tandem Computers Incorporated
Wait Completion Mode In the wait completion mode, SNAX/HLS returns control only when the requested
operation is complete. Note that this can involve a long delay, especially for those
operations that depend upon actions from the session partner. The wait mode is
available on the HLS-OPEN, HLS-CLOSE, HLS-DEALLOCATE, HLS-RESPOND, and
HLS-FLOW-CONTROL requests. The flow of a wait operation is shown in Figure 4-2.
Figure 4-2. Flow of a Wait Operation
USER SNAX/HLS
:
:
develop verb+msg
:
:
CALL WRITEREAD
syntax checks
resource checks
FSM checks
state checks
SNALU interface
(wait for response)
analyze response
(read completes)
:
:
interpret verb return code
:
Queued Completion Mode In the queued completion mode, SNAX/HLS returns control as soon as the requested
operation is initiated. The return code is unique to this situation; it is
RC-FORTHCOMING. When the action eventually completes, a queued completion
notice is queued to the session that might be retrieved by the application by a
subsequent RECEIVE-DATA, RECEIVE-CONTROL, RECEIVE-CONTROL-WAIT, or
SEND-AND-RECEIVE-DATA request. The queued mode of operation is available on
HLS-OPEN, HLS-DEALLOCATE, HLS-CLOSE, and HLS-FLOW-CONTROL requests.
The flow of a queued operation is shown in Figure 4-3.