Listing a Registered Event

You can register an event by adding a template file entry as described in “Event Templates”, and entering the evmreload command with the -d option to make the events known to the Event Manager daemon, or restarting the system.

You can use the evmwatch -i command to retrieve a list of registered events. Pipe the output from the evmwatch -i command to the evmshow command to display the event templates in any desired format. For example:

	 # evmwatch -i | evmshow -t "@name [@priority] @format" -x

Templates are returned as binary events which you can either redirect in to a file or pipe to the evmshow command for display. In the previous example, the show-template (t option) displays the name of the event, the priority, and the message format. The x option causes each summary line to be followed by an explanation of the event.

You must specify a command sequence that requests only the event's message format, not an expanded message, because you are displaying templates (not real system events). In the output, the summary lines display the messages with names of variables rather than their values, as shown in the following summary line and explanation:

	 	 sys.unix.procsm.category.create[200] ProcSM:A category “$_catname” has been added. 
This informational event is posted by ProcSM module to indicate that a new category has been added to Process Set Manager.

In this example, the $_catname variable is replaced by the category name when you use the evmget command to retrieve a posted instance of the event.

If you do not want to see all registered events, use a filter to limit the output of the evmwatch command to the events in which you are interested, as follows:

	 # evmwatch -i -f '[name *.evm]' | evmshow -t "@name \
	 	 	 [@priority] @format" -x 

Using the -A Option to Simplify the Command String

The Event Manager commands are designed to be building blocks, with each command performing a specific operation. This provides you with flexibility in developing shell scripts to manipulate event information. When you enter commands from the command line, you may prefer to simplify the command.

The most common command sequence for event retrieval is the evmget command, piped in to the evmsort command, piped in to the evmshow command. You can then pipe the text output in to the more command to display the output. Consider the following example:

# evmget -f '[pri >= 600]' | evmsort -s "priority-:timestamp+" | evmshow | more

You can simplify the previous command by using the evmget
-A command option, which automatically pipes the command output to other Event Manager commands. For example, you can use the -A option to simplify this command as follows:

# evmget -A -f '[pri >= 600]' -s "priority-:timestamp+" | more

When the evmget -A command starts, it automatically runs the evmsort -A command, and pipes its output in to that command. When the evmsort command starts, the A option causes it to start the evmshow command, piping events into it for display. You can supply a sort specification with the s option and a show-template with the t option. These options are sent to the evmsort command and evmget commands, respectively.

The evmwatch command supports the -A described in “Monitoring Events”.