SPI Common Extensions Manual

Extended SPI Concepts
SPI Common Extensions Manual—427508-001
2-3
Special Object Types NULL and SUBSYS
•
A token (ZCOM-TKN-SUBJ-objtype), which conveys the type and name of an
object that is the subject of an event message.
Example: Assigning Object Types
To put an object type into a command message with SSINIT and to retrieve an object
type with SSGETTKN:
INT object^type;
status := SSINIT(message^buffer
,message^buffer^len
,ssid
,ZSPI^VAL^CMDHDR
,ZCOM^CMD^command
,ZCOM^OBJ^objtype);
status := SSGETTKN(message^buffer
,ZCOM^TKN^OBJTYPE
,object^type);
For a complete list of common object types and their descriptions, see ZCOM Object
Types on page 4-20.
Special Object Types NULL and SUBSYS
The object types NULL and SUBSYS have strictly regulated meanings and are used
only in certain circumstances:
Object-Type Hierarchies
A subsystem can subordinate a particular object type to another type, thereby
establishing a hierarchy of object types. A command can then be applied to an object,
its subordinates, or both, by using the ZCOM-TKN-SUB (subordinate) command
modifier.
ZCOM-OBJ-NULL Must not be assigned to any defined object. Use it only in the
GETVERSION, LISTOBJECTS, and AGGREGATE commands
when object type is irrelevant or unknown.
ZCOM-OBJ-SUBSYS If used, must be the highest type in the hierarchy of objects defined
by a subsystem, often representing the subsystem or subsystem
manager process itself (the native object).