SNAX/XF and SNAX/APN Event Management Programming Manual

Glossary
SNAX/XF and SNAX/APN Event Management Programming Manual—426859-001
Glossary-7
error number
other error lists. The return token cannot be included in an error list. See also return
token.
error number. A value that can be assigned to a return token, or to the last field of an error
token, to identify an error that occurred. Some error numbers are defined in the SPI
common extensions (ZCOM) definitions; others are defined by individual subsystems.
error token. A token in a response message that indicates the reason an error occurred during
processing of a programmatic command. Compaq subsystems enclose each error token
in an error list, which can also contain additional information about the error. A response
record must contain a return token and can also contain error lists to explain the error
further. The token code for the error token is ZSPI-TKN-ERROR. Its value is a structure
consisting of the subsystem ID and an error number identifying the error. See also error
list, error number, and return token.
event. A significant change in some condition in the system or network. Events can be
operational errors, notifications of limits exceeded, requests for action, notifications of
lines and other objects becoming available, and so on. Note that an event is not always
an error.
event log. A file or set of files maintained by EMS to store event messages generated by
subsystems.
event management. The reporting and logging of important events that occur in a system or
network, the distribution and retrieval of information concerning those events, and the
actions taken by operations personnel or software in response to the events. See also
control and inquiry
.
Event Management Service (EMS). A part of DSM used to provide event collection, event
logging, and event distribution facilities. EMS provides for different descriptions of
events for people and for programs, lets an operator or application select specific event-
message data, and allows for flexible distribution of event messages within a system or
network. EMS has an SPI-based programmatic interface for reporting and retrieving
events.
event message. An SPI message that describes an event occurring in the system or network.
event token. A token containing information pertaining to an event.
exception response mode. A mode in which a response from the device is sent only if an
error is detected. See also definite response mode
.
execute I/O (EIO). A machine instruction on the Compaq processor that initiates a transfer
over the I/O channel.
Expand network. A network consisting of Compaq systems interconnected by
communication links and supported by Expand software.
Expand networking software. Compaq software that can connect up to 255 Compaq
NonStop™ systems or servers into a single network.