Go to main content

ONC+ RPC Developer's Guide

Exit Print View

Updated: November 2020

ONC+ RPC Glossary


A process that remotely accesses resources of a computer server.

client handle

A client process data structure that represents the binding of the client to a particular server's RPC program.

connectionless transport

Characteristic of the model of interconnection in which communication takes place without first establishing a connection. See datagram transport.

connection-oriented transport

Characteristic of the model of interconnection in which communication proceeds through three well-defined phases: connection establishment, data transfer, and connection release. See stream transport.

datagram transport

A message and the Internet source and destination addresses that are associated with it. Datagram transports have less overhead than connection-oriented transports but are considered less reliable. Data transmissions are limited by buffer size.


To convert data from XDR format to a system-specific representation.


An abstraction used by the service libraries to refer to a file or a file-like object such as a socket.


A computer system that is accessed by computers and/or workstations at remote locations. Usually the host contains the data, but in networks, the remote locations can be the host and provide information to the network.

MT hot

Characteristic of an interface in which the library or call automatically creates threads.

MT safe

Characteristic of an interface that can be called in a threaded environment. An MT-safe interface can be invoked concurrently for multiple threads.

network service

A collection of one or more remote service programs.


A service that verifies activity on a remote system. A computer sends a small program to a host and notes time on its return path.

RPC language (RPCL)

A C-like programming language translated by the rpcgen compiler. RPCL is a superset of XDR Language.

RPC library

The network services library, libnsl, specified to the link editor at compile time. Also known as the RPC package.

RPC protocol

The message-passing protocol that is the basis of the RPC package.


A standard for system-independent data structures. See RPC language.


To convert data from a system representation to XDR format.


The fourth layer of the Open Systems Interconnection (OSI) Reference Model.

transport handle

An abstraction used by the RPC libraries to refer to the transport's data structures.


Transport-independent RPC. This is the current version.


Transport-specific RPC. This is an older version. It is still supported, but TI-RPC is preferred.

universal address

A hexadecimal address of a type of network, such as TCP/IP, that configures the port monitor to check for print requests from print clients on a network.

virtual circuit transport

An apparent connection between processes that is facilitated by transmission control protocol (TCP). A virtual circuit enables applications to "talk" to each other as if they had a physical circuit.

XDR Language

A data description language and data representation protocol.