SNAX/HLS Application Programming Manual

HLSCLOSE Verb
SNAX/HLS Verbs
104707 Tandem Computers Incorporated 5–17
HLS-CLOSE Verb The HLS–CLOSE verb breaks the connection between the partners of the session. If
more than one connection has opened the session, only the last HLS–CLOSE request
actually performs the close. The requester must be an opener of the session.
This verb need not be used unless your application needs to retain the LU in an
allocated state (see HLS–DEALLOCATE verb, below).
Application programs that attempt to re-establish a session using HLS–CLOSE and
HLS–OPEN without an intervening HLS–DEALLOCATE and HLS–ALLOCATE
should be aware that HLS–CLOSE does not purge the queue of data awaiting delivery
to the application program. Thus, unless precautions are taken, data received while an
earlier session was in effect may be interpreted as arriving during a new session.
The precautions include the following
Use HLS–DEALLOCATE and HLS–ALLOCATE to discard all queued data.
Discard all queued data prior to reopening the session. You can accomplish this
by using the following algorithm:
Issue HLS–CLOSE to close the old session.
Loop while RECEIVE–CONTROL indicates data present.
If application data is indicated,
Issue RECEIVE–DATA to accept the data
Ignore the data
End loop
Issue HLS–OPEN to initiate a new session.
HLS–CLOSE can only be used if the HLS–OPEN verb opened the session.