SPI Common Extensions Manual

Extended SPI Concepts
SPI Common Extensions Manual—427508-001
2-7
Commands
Commands
Commands specify the type of processing to be performed on objects. For descriptions
of the common commands listed here, see Section 5, Commands and Responses. For
a list of the common commands, see Table 5-2 on page 5-9.
A command is contained in a command message, which is identified by the value
ZSPI-VAL-CMDHDR in the message header. ZSPI-VAL-CMDHDR is put into the
message header with the SSINIT procedure. The SSINIT procedure assigns the value
ZSPI-VAL-CMDHDR to ZSPI-TKN-HDRTYPE.
Specify a command in a request by assigning a value ZCOM-CMD-command to the
token ZSPI-TKN-COMMAND. Your application calls the SSINIT procedure to put
ZCOM-CMD-command into the command-message header:
status := SSINIT(message^buffer
,message^buffer^len
,ssid
,ZSPI^VAL^CMDHDR
,ZCOM^CMD^command);
Order of Execution
The order in which a command is applied to objects in a hierarchy depends on the
subsystem implementation of the command.
Assume the object hierarchy:
LINEs A
PUs D E
LUs K L N O
A START command applied to all of these objects might start them in the order A, D, K,
L, E, N, O.
A STOP command applied to all of these objects might stop them in the order K, L, D,
N, O, E, A.
The implementation of a hierarchy, including the definition of those situations that result
in an error, is subsystem-specific.