contain log messages
that you create using the SAS logging facility. Logging facility messages
can be created within SAS programs or they can be created by SAS for
logging SAS server messages. Logging facility log messages are based
on message categories such as authentication, administration, performance,
or customized message categories in SAS programs. In SAS programs,
you use logging facility functions, autocall macros, or DATA step
component objects to create the logging facility environment.
The logging facility
environment consists of loggers, appenders, and log events. A logger
defines a message category, references one or more appenders, and
specifies the logger's message level threshold. The message level
threshold can be one of the following, from lowest to highest: trace,
debug, info, warn, error, or fatal. An appender defines the physical
location to write log messages and the format of the message. A log
event consists of a log message, a message threshold, and a logger.
Log events are initiated by SAS servers and SAS programs.
When SAS processes
a logging facility log event, it compares the message level in the
log event to the message threshold that is defined for the logger
that is named in the log event. If the log event message threshold
is the same or higher than the logger's message threshold, the message
is written to the locations that are specified by the appenders that
are referenced in the logger definition. If the log event is not accepted
by the logger, the message is discarded.
Appenders are defined
for the duration of a macro program or a DATA step. Loggers are defined
for the duration of the SAS session.