SNAX/HLS Application Programming Manual

SEND-DATA-Verb
SNAX/HLS Verbs
5–104 104707 Tandem Computers Incorporated
If RETURN–CODE contains any value other than those listed above, this field is
undefined and should not be analyzed.
USER–ERROR–CODE
contains the second two bytes of SNA sense data if the SYSTEM-ERROR-CODE
contains the first two bytes of SNA sense data.
RETRY–ACTION–CODE
is a summary indicator that indicates whether an unsuccessful request should be
retried. The value returned here can be installation–defined.
RECOVERY–TAGS
are returned to allow the requester to correlate requests, SNA responses, and/or
SNAX/HLS replies. BOM is the SNA sequence number of the first element of the
data message. EOM is the SNA sequence number of the last element of the data
message.
When delayed request mode is used (a BIND–specified mode of operation that
permits more than one request at a time to be outstanding), two SEND–DATA
replies can be generated as the result of one SEND–DATA (or
SEND–AND–RECEIVE–DATA) verb. The first indicates that the message has
been sent and has RECOVERY–TAGS values that properly delineate the message
just sent. If the first reply indicates RC–OK, then a second reply is expected and
can be obtained by the program in response to a RECEIVE–DATA,
RECEIVE–CONTROL, or a RECEIVE–CONTROL–WAIT verb. This second reply
indicates the receipt of a response from the partner and has a RETURN–CODE
value of either RC–NOTIFICATION or RC–REQUEST–REJECT. Assuming that the
partner obeys the rules of SNA, the response can arrive only in response to a
definite–response chain or as an error response to an exception–response chain.
Under these circumstances, SNAX/HLS cannot guarantee the correctness of the
values in the RECOVERY–TAGS. The single value received in the response is
returned in both the BOM and EOM fields of the response. The specific value is
customarily the EOM value, but the formal protocol permits any value between
the BOM and EOM values.
RECEIVE–DATA–QUEUED.
A value of Y indicates that data is available on the user’s receive queue. In this
situation, RECEIVE–DATA verbs completes immediately (that is, with no internal
queuing) until the indicator is N.
ENTER–RECEIVE–STATE–IND.
A value of Y indicates that the session partner has sent ATTENTION and requests
the requester to set PREPARE–TO–RECEIVE–IND to Y on a SEND–DATA verb
when convenient (used only for HDX protocols).
A value of Y occurs in the following contexts: