SNAX/APC Management Programming Manual

Interfaces to SNAX/APC
Introduction to SNAX/APC
1–2 111813 Tandem Computers Incorporated
Interfaces to
SNAX/APC
Figure 1-1 shows SNAX/APC and its DSM interfaces. The SNAX/APC Planning and
Configuration Manual and the SNAX/APC Application Programming Manual describe
SNAX/APC and its architecture in much greater detail.
Figure 1-1. Interfaces to SNAX/APC
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Event
Application
DSM
Application
SCP SCF
SNAX/APC
EMS
DSM applications involved in configuration and control activities and the SCF
interface communicate directly with the Subsystem Control Point (SCP). SCP then
passes message buffers on to SNAX/APC through the pseudodevice
$snax/apc-process.#ZSPI.
A DSM application can create a consumer distributor and use EMS to handle events.
This is discussed in more detail in “Event Messages,” later in this section.
For discussions on how to use the DSM programmatic interface to SNAX/APC, see the
SPI Programming Manual and the SPI Common Extensions Manual.
Relationship of
Applications to the
SNAX/APC Subsystem
DSM management programming applications do not communicate directly with the
SNAX/APC subsystem. Instead, an application typically sends a request to the SCP,
which examines the request, determines its destination data communications
subsystem (in this case, SNAX/APC), and sends it to the indicated subsystem.
When the SNAX/APC subsystem finishes processing a request, it returns the response
to the SCP, which then returns the response to the application.