Distributed Name Service (DNS) Management Programming Manual

Retrieving and Decoding Event Messages
SPI Programming Considerations for DNS
46958 Tandem Computers Incorporated 3–13
Filters EMS provides you with the ability to create filters, which allow applications to select
particular event messages from among those reported. Filters select messages to be
returned to an application by examining the values of tokens in the messages. For
example, to select only event messages reported by DNS, a filter would examine the
token that contains the subsystem ID of the issuing subsystem and then allow only
those messages containing the DNS subsystem ID to pass.
You can create a filter in the EMS filter language, compile the filter source file with the
EMS filter compiler, and load the resulting filter when you run the EMS consumer
distributor. Also, you can replace filters online.
You can use any of the tokens contained in event messages to select which event
messages will be returned to your application. You can create filters that return only
critical event messages, all messages with a certain event number, and so forth.
The Event Management Service (EMS) Manual provides information on how to code,
compile, load, and replace filters.