SNAX/APN Application Programming Manual

The SNALU Interface
SNAX/APN Application Programming Manual—420111-001
4-15
SNALU Application Initiates Session With Remote
PLU
SLU Acquire mode. For information about the character-coded logon request, see
Character-Coded Logon Requests on page 4-16.
The sequence of events for SLU Acquire are as follows:
1. The application opens the SNALU LU.
2. The application formats an INIT-SELF request or character-coded logon request and
sends it to the SLALU LU that was just opened.
3. When the INIT-SELF request is received, the application must issue a
WRITEREAD and wait for the INIT-SELF or character-coded logon response.
4. The BIND request is eventually sent to the SLU by the PLU.
Upon receipt of a positive INIT-SELF response from SNAX/APN, the application
should issue another WRITEREAD to the SNALU LU.
The DLU name field of the INIT-SELF request or a character-coded logon request can
contain either the SNA name of a remote PLU, or a zero-length field, that is no DLU
name is provided. If the DLU name is not provided, the SNANAME of the SNALU LU
will be used as the PLU name.
The application may receive a Network Services Procedure Error (NSPE) request if
either of the following occurs:
•
The timer expires when receiving the BIND from the PLU, and an INIT-SELF
request was sent.
•
There is a problem generating or receiving the CINIT request to the PLU, and an
INIT-SELF request was sent using format 0.
The application may receive a NOTIFY request if either of the following occurs:
•
The timer expires when receiving the BIND from the PLU, and a character-coded
logon request was sent.
•
There is a problem generating or receiving the CINIT request to the PLU, and an
INIT-SELF request was sent using format 1 or 2, or a character-coded logon request
was sent.
For illustrations of situations in which SLU Acquire is used, see Appendix C, Logic
Flows and Internal Formats When Using SNALU.
INIT-SELF Request Formats
There are three forms of the INIT-SELF request: format 0, format 1, and format 2. The
three formats are very similar to one another. The specific parameters contained in each
of the formats is shown in Figure 4-5.