OSF DCE Application Development Guide--Core Components

OSF DCE Application Development Guide—Core Components

4.3.4 Howto Route Messages

Serviceability messages can be written to any of the normal output destinations. Routing

for serviceability messages can be speciﬁed in any of three different ways (in ascending

order of precedence):

1. By the contents of a routing ﬁle

2. By the contents of a routing environment variable

3. By calling the dce_svc_routing() routine (often as part of processing an

application’s command-line arguments)

Additional routing (that is, in addition to whatever routing has been speciﬁed by the

means described) of a message to standard error can be performed in either of the

following two ways:

• By specifying the routing as one of the message’s attributes (in the sams ﬁle

deﬁnition of the message)

• By specifying the attribute in the call to dce_svc_printf( ) (or other serviceability

output routine) to generate the message

Routing a message actually consists of specifying two things:

• How the message should be processed (the form it should be put in)

• Where the message should be sent (its destination)

The two speciﬁcations are sometimes closely interrelated, and sometimes specifying a

certain destination implies that the message must be put into a certain form. This fact

allows certain combinations of processing and destination to be abbreviated.

In the following sections, each of the ways to route serviceability messages is described.

Note that debug messages are routed by a similar, but slightly different, technique. For a

full description, see Section 4.3.12.

4.3.4.1 Using a Routing File

If a ﬁle called dce-local-path/svc/routing exists, the contents of the ﬁle (if in the proper

format) will be used to determine the routing of messages written via serviceability

routines.

The value of dce-local-path is usually /opt/dcelocal; the default location of the

serviceability routing ﬁle is usually /opt/dcelocal/svc/routing. However, a different

location for the ﬁle can be speciﬁed by setting the value of the environment variable

DCE_SVC_ROUTING_FILE to the complete desired pathname.

The contents of the routing ﬁle consists of formatted strings specifying the routing

desired for the various kinds of messages (based on message severity). Each string

consists of three ﬁelds as follows:

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