evmtemplate(4)evmtemplate(4)NAMEevmtemplate - Event Manager template file
SYNOPSISDESCRIPTION
A template event is a description of an event that is held centrally by
EVM. The template is used for the following purposes:
· To register the event with the EVM daemon, so that it will
allow the event to be posted.
· To centralize event information. This makes it easy to
review and maintain details such as the associated message
text and the event priority, and minimizes the amount of
information that must be hard-coded into an application.
File Format
On startup, and each time the command is run, the EVM daemon reads all
valid event template files stored in the template directory tree rooted
at or in any directory tree linked to that directory, including the
local template tree rooted at There is no limit to the number of tem‐
plate files that can be installed in the tree, or to the number of tem‐
plates that can be included in each file.
Template file names must end with the suffix and the files must be
owned by or and must have permissions of or to be recognized. If tem‐
plate files are added, deleted or modified while the daemon is running,
the command should be used to instruct the daemon to reconfigure
itself. Refer to the evmreload(1M) manpage for more information.
Every template event must contain a data item with at least two compo‐
nents. A template typically also contains constant items such as the
event priority and the message format string.
When a client posts an event, it must include in the posted event a
name with at least three components. The posted event also typically
contains any applicable variable data along with environmental items
such as a timestamp and the name of the posting system.
When the EVM daemon receives a posted event, it searches its template
database for the template event whose name best matches the name in the
posted event. If it cannot find a matching template, the daemon
rejects the posting attempt. Otherwise, the daemon merges the data
items held in the two versions of the event, yielding a merged event
which it distributes to subscribers.
A template event name does not have to be identical to the name of a
posted event to be considered a match. If it has fewer name components
than the posted event, a template event is still considered a match if
all components in the template name exactly match their equivalent com‐
ponents in the posted name. If the template name is longer than the
name of the posted event however, it cannot be a match. In determining
the template that best matches the name of the posted event, the daemon
selects the matching template with the most components.
The following table shows some examples of event name matching. In the
final example, the template does not match the posted event because the
template has too many components.
Posted Name Template Name Match?
───────────────────────────────────────────────────────────────
myco.myprod.env myco.myprod.env Yes
myco.myprod.env.temp.high.70 myco.myprod.env Yes
myco.myotherprod myco.myprod No
myco.myotherprod myco.myotherprod.start No
The syntax of an event template file is identical to the syntax of a
file given as input to the command. The following keywords may be
specified in a template file:
This keyword introduces an event group.
The body of the group is delimited by braces.
Names the template event.
The name must be made up of two or more components containing
only alphanumeric and underscore characters, and separated by
dot characters.
Event format text.
The format_specifier is a string that will be used to produce
a formatted message for display if the event is passed
through the command, or the library function. See the
evmshow(1) and EvmEventFormat(3) manpages.
If a format_specifier contains no special characters, it is
displayed unchanged as the event's message text. For exam‐
ple, if encounters an event containing the following simple
format_specifier, it displays the string exactly as speci‐
fied:
If the format_specifier contains variable-specifier in the
form and either the posted event or the template event con‐
tains a variable with that name, the variable_value will be
included in the formatted output in place of the variable-
specifier. If no such variable is present, the variable-
specifier is included in the output. For example, if an
event contains a variable called and the format_specifier:
then might display the event as:
If the format_specifier contains a data-item-specifier in the
form the data-item-specifier is replaced with the value of
the corresponding data item from the event. For example, if
an event contains a variable called and the format_specifier
is:
then might display the event as:
If the data item is not present in the event, a hyphen char‐
acter is output in its place. An character that is not asso‐
ciated with a valid item name is unchanged in the output.
Any characters in the format_specifier that are not part of a
variable_name or data-item-specifier are output unchanged.
If no format_specifier is supplied in either the template
file or the posted event, a default event message is used
when the event is formatted for display.
Indicates the importance of the event, but does not affect the order of
event distribution. The priority must be an integer value in
the range 0 (lowest) to 700. See the EvmEvent(5) manpage for
the meanings of specific priority values.
The name of an I18N catalog file holding text strings to be displayed
in
place of the strings contained in the event. This item is
used for internationalizing events. If it is omitted, the
strings contained in the event will be used when the event is
formatted for display. Refer to the for more information.
Identifies the message set within the
i18n_cat to be used for translation of all internationalized
strings in the event. This item is ignored if no i18n_cat is
supplied.
Identifies the I18N catalog message to be used in place of the
data item when the event is formatted for display. This item
is ignored if no i18n_cat is supplied. If an i18n_set has
been specified, the i18n_msg must refer to a message identi‐
fier within the given set. If the catalog is missing, or if
the i18n_set or i18n_msg values do not refer to a message in
the catalog, the event's data item is used.
This text string is intended to be used by an event channel's
explanation function to retrieve explanation text for the
event. The format of the string is defined by the event
channel.
This keyword introduces a variable group, with the body of the group
being delimited by braces. An event may include any number
of variable groups.
Although actual variable values are most likely to be
included in the posted version of an event, and will override
the values specified in the template version, it is usually
helpful to include the variables in the template event as
well, specifying dummy values such as zero, to provide docu‐
mentation of the expected contents. For example, the tem‐
plate version will be seen if the results of an command are
piped into
The following keywords are recognized in a variable group:
The name must be made up of alphanumeric and underscore char‐
acters.
The type of the variable item.
See the EvmEvent(5) manpage for a list of types.
All EVM variable types may be specified except for
If this keyword is omitted a type of is assumed.
Value for the variable.
A value must be specified in the template, but usu‐
ally should be overridden by the value in the
posted version of the event. Values supplied in
the template should be default or nonnormal values
that will be recognized as incomplete when the
event is interpreted.
For variables, the i18n_msg identifies the I18N catalog
message to be used in place of the variable_value
when the event is formatted for display. This item
is ignored if no i18n_cat is supplied for the
event. If an i18n_set has been specified, the
i18n_msg must refer to a message identifier within
the given set. If the catalog is missing, or if
the i18n_set or i18n_msg values do not refer to a
message in the catalog, the variable_value is used.
Any items specified outside an group are global items, which will be
included in each following template that does not include them explic‐
itly.
Notes
If you are concerned with allowing your file to be used on other sys‐
tems that support EVM in the future, you should use the built-in macro
in place of the first two components of the name of any system event.
This will make it unnecessary to change the file if the other system
uses a different event name prefix.
EXAMPLES
The following file is an example of an event template file.
FILES
The root of the directory tree containing system event template files.
The root of the directory tree containing local event template files.
This directory is accessed from the system template directory
through a symbolic link.
SEE ALSO
Commands
evmpost(1), evmshow(1), evmd(1M).
Routines
EvmEventCreate(3), EvmEventDump(3), EvmEventFormat(3), EvmEventPost(3),
EvmItemSet(3).
Files
evmdaemon.conf(4).
Event Management
EVM(5).
EVM Events
EvmEvent(5).
evmtemplate(4)
