OSF DCE Application Development Guide--Core Components

Chapter 4. Using the DCE Serviceability

Application Interface

DCE serviceability was originally developed simply as a way of standardizing server

messages. The goal of its design was to make sure that all situations requiring human

intervention that can be encountered by a server are documented and identiﬁed (both by

the server when reporting them, and by the documentation when explaining them) in a

standard coordinated way so that system administrators can easily determine the proper

corrective action to take in response. Both the server message text and the relevant

documentation are derived from the same source (that is, a .sams input ﬁle), which

minimizes the possibility of any discrepancies appearing between the two.

The serviceability component is used by the DCE components (RPC, DTS, Security, and

so on) for their server messaging, and it is made available as an API for use by DCE

application programmers who wish to standardize their applications’ server messaging.

(The DCE components are required to use the serviceability routines, but applications

are not.)

4.1 Overview

Serviceability uses XPG4 message catalogs to hold message text, but it adds an

additional layer to the XPG4 functionality. The message catalogs and other required

data (and documentation) ﬁles are generated by a utility called sams (‘‘symbols and

message strings’’). Its input is a text ﬁle that establishes some organizational

information about the program that is to use the messages, followed by a series of

speciﬁcations of the messages themselves.

Each message speciﬁcation contains, along with the message text itself, a detailed

explanation of the situation in which the message will be displayed, together with a

description of the action required, where applicable, to correct the situation. Part of the

output of sams thus consists of ‘‘automatic’’ documentation of all the messages writable

via the serviceability API. This output was used as the basis of the contents of the for the

DCE component server messages.

Messages also have one or more attributes speciﬁed in the sams input ﬁle. The

attributes fall into three broad categories: those that indicate message severity, those that

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