SNAX/HLS Management Programming Manual

Standard SNAX/HLS Definitions
Common Definitions
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When chaining is disabled, the size of messages is limited to the value given by the
ZMAX–RU value. The actual value indicated here corresponds to the value
included on the BIND record. Selecting some FM profiles overrides the value of
this field.
This field can have the following enumerated values:
ZHLS–VAL–CHAIN–USE–MULTI
specifies that multiple–element chains are used.
ZHLS–VAL–CHAIN–USE–SINGL
specifies that only single–element chains are used.
ZCMPRSS–IND
specifies whether data compression is used by the primary half session. The value
ZSPI–VAL–TRUE means compression is used; the value
ZSPI–VAL–FALSE means it is not used. This value is set when the BIND message
is processed. Compression is often used in file–transfer protocols—in particular,
with LU type 1 and RJE sessions. SNAX/HLS neither enforces nor interprets this
value; interpretation is application dependent.
ZEB–SEND
indicates whether the half session sends an end brackets indicator (EBI). If either
or both of the EBI indicators are set, brackets are in use for the session. If neither
the primary nor the secondary half session can send an EBI, no brackets are in use.
The usual situation is that the primary can send an EBI but the secondary cannot,
reflecting the fact that the primary is in control of transaction binding.
The value ZSPI–VAL–TRUE means this half session can send an EBI. The value
ZSPI–VAL–FALSE means this half session never sends an EBI.
Note Brackets are an SNA concept relating to logical units of work, frequently associated
with transactions. Brackets are not used on all sessions. When used, one partner is
known as the “first–speaker” and the other as the “bidder.” The distinction is set at
session establishment (BIND request). SNAX/HLS uses the bracket state manager
rules appropriate to the half session.
ZRQ–MODE
specifies whether the half session uses immediate or delayed request mode. This
value is set when the BIND message is processed and is one of the following
enumerated values:
ZHLS–VAL–RQ–MODE–DELAYED
specifies that delayed request mode is used. This protocol allows multiple
outstanding definite response chains at any one time.