Expand Management Programming Manual

ELEMENTS OF SPI MESSAGES FOR THE EXPAND SUBSYSTEM
Event Numbers
Event Numbers
Event numbers for event messages issued by the EXPAND subsystem
are represented by symbolic names of the form ZEXP-EVT- name ,
where name identifies the event. EXPAND event numbers and their
associated event messages are described in Section 8, "Event
Management."
Subjects of Event Messages
In EXPAND event messages, there are two possible forms for the
subject token (the token that immediately follows the subject-
mark token), depending on whether the subject is a logical device
or a system.
When the subject of an event is a logical device, the subject
token is a device-name token that contains an 8-byte GUARDIAN
internal-format device name.
When the subject of an event is a system, the subject token
is a system-name token that contains the name of the system as
a string of eight ASCII characters. In this case, the event
message also contains a system-number token that gives the system
number of the system as a 16-bit signed integer.
Other Tokens
In addition to the tokens already described, the EXPAND subsystem
uses other tokens as command parameters, results in responses,
and elements of event messages and error lists.
Simple Tokens
Simple tokens--tokens whose values are single fields or fixed
structures--are identified by token codes. The token codes for
the simple tokens used by the EXPAND subsystem are represented
by symbolic names of the form subsys -TKN- name , where subsys
is a four-character subsystem abbreviation and name identifies
the token code. For example, the token code ZEXP-TKN-SYSNAME
identifies a simple token that contains the name of a system.
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