SNAX/HLS Application Programming Manual

RECEIVE-CONTROL-WAIT Verb
SNAX/HLS Verbs
5–76 104707 Tandem Computers Incorporated
In some cases (most noticeably, in TSO sessions), you might receive
two copies of the message because your partner issued a temporary
UNBIND command and then rebound the session.
9 (Name is DT–SESSION–CLOSED.) The session has just been closed
by partner. The message contains information indicating why the
session was closed. This message can be delivered only if you
created the session with the HLS–ALLOCATE and HLS–OPEN
verbs.
It is highly unlikely that your application needs to know the precise
reason that the session was closed, but, if it does, the data–reply area
contains the actual SNA message unit that caused the closure. For
example, if the closure occurred because your partner issued a
normal UNBIND command (this can happen only if you are
secondary), you receive a 2–byte message containing the value
%H3201.
10 (Name is DT–FLOW–CONTROL.) This occurs only if the receipt of
flow control messages has been enabled for the receiving half–
session. Such messages are enabled based upon the
WANT–FLOW–CONTROL attribute in the PROFILE, or by the
issuance of the SM (Stop Messages) request. It indicates that one of
the four supported flow control signals has been received. The
specific signal is indicated by the contents of the data field, which
contains two characters, as follows:
RT (SNA RTR message.) This message was sent by your partner to
invite you to begin new transactions. You need not actually
honor the request. However, it could be used to cause your
application to retry sending an old transaction that was rejected
with an %H0813 or %H0814 sense code.
SM (SNA QEC message.) This message was sent by your partner to
request that you stop sending new messages. This is frequently
used because your partner is temporarily congested. If you are
using LMO and have begun a message, you can send the
remainder of the message (up to and including the element that
carries the MESSAGE–COMPLETE–IND set to Y). Once the end
of the current message has been sent, or if you are not using
LMO, no more data traffic is accepted. The only acceptable
action at this point, other than session termination, is to issue
the HLS–FLOW–CONTROL verb using QM as the argument.
QM (SNA QC message.) This message was sent by your partner in
response to an HLS–FLOW–CONTROL verb (using SM) that
you sent. It confirms that your partner sends no more
messages until you send the resume signal, HLS–FLOW–
CONTROL(RM).