OSF DCE Application Development Guide--Introduction and Style Guide

Introduction to DCE Application Programming
reference the application code needs to access the interface handle. The interface handle
allows the application code to refer to the interface specification in calls to the RPC
runtime. Runtime operations obtain required information about the interface, such as its
UUID and version numbers, directly from the interface specification.
You run the IDL compiler by issuing the idl command. See the idl(1rpc) reference page
for a description of the idl command and its options.
1.3.4 The Attribute Configuration File
Application developers can use an optional attribute configuration file to tailor how an
RPC interface appears to local application code and how the local application code
interacts with the RPC interface. The attribute configuration file is written in the
attribute configuration language, which is a companion language to IDL. When the IDL
compiler is invoked, it searches for an attribute configuration file in addition to
processing the interface definition file.
An attribute configuration file modifies how the IDL compiler interprets an interface
definition. For example, an attribute configuration file can specify a subset of operations
declarations for a client stub so that the client stub contains declarations for only the
operations that the client application code needs for its remote procedure calls. Limiting
the client’s access to the remote procedures offered by servers reduces the size of the
client stub. Another action you can control with an attribute configuration file is defining
how a client establishes a binding with a server that implements the called interface.
For complete information on the set of attribute configuration file attributes, see the .
1.3.5 The DCE Host Daemon
Each DCE host runs a DCE host daemon (dced) to provide remote DCE management
services for a host and its servers. The dced provides remote management of DCE-
related host and server data, it provides remote control of a host’s servers, and it
maintains host-specific state for DCE such as the host’s login identity. From the server’s
perspective, dced is a central point where all servers can consistently inform their host
about themselves. From the host’s perspective, dced gives clients, management
applications, and DCE administrators (via dcecp) a focal point from which to find out
about (and even control) servers.
The most important feature of the dced is that it provides the endpoint mapper service.
This service maintains the host’s local endpoint map for local RPC servers and looks up
endpoints for RPC clients. An endpoint is the address of a specific instance of a server
that is executing in a particular address space on a given host. Each endpoint can be
used on a host by only one server at a time. The endpoint map is the system-specific
database on each host, in which servers register their endpoints and associated
addressing information (information about communication protocols, objects, and so on).
A server registers separate endpoints for each of its RPC interfaces and any objects the
server offers with the interface.
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