NonStop System Glossary

shared memory
An interprocess communication mechanism that allows two or more processes to share a given
region of memory.
Shared Millicode Library
An intrinsic library containing privileged or TNS-derived millicode routines used by many
native-compiled programs and by emulated TNS programs. This library includes efficient string-move
operations, TNS floating-point emulation, and various privileged-only operations. These routines
are mode independent. They comply with native calling conventions but can be directly invoked
from any mode without changing execution modes.
shared run-time library (SRL)
A collection of procedures whose code and data can be loaded and executed only at a specific
assigned virtual memory address (the same address in all processes). SRLs use direct addressing
and do not have run-time resolution of links to and from the main program and other independent
libraries. Contrast with dynamic-link library (DLL). See also TNS shared run-time library (TNS SRL)
and TNS/R native shared run-time library (TNS/R native SRL).
shell
1. In the Open System Services (OSS) environment, a program that interprets sequences of text
input as commands. A shell can operate on an input stream, or it can interactively prompt and
read commands from a terminal.
2. An envelope of code that provides a convenient way to call a procedure in another execution
environment. See also TNS to native-mode access shell.
shell generator
A software tool that, given a procedure interface definition coded in pTAL for a native-mode library
procedure, produces a custom shell routine to provide access from TNS object code to that
native-mode procedure. See also TNS to native-mode access shell.
shell map
An address table created by the NonStop operating system that contains the entry point addresses
of all available TNS to native-mode access shells. See also TNS to native-mode access shell.
shielded twisted pair (STP)
A transmission medium consisting of two twisted conductors with a foil or braid shield. Contrast
with unshielded twisted pair (UTP).
shutdown file
A file invoked by the local operator or by another shutdown file that contains commands to shut
down system devices, communications lines, and system and application software. Contrast with
startup file.
SID
See system image disk (SID) or source ServerNet ID (SID).
signal
The method by which an environment notifies a process of an event. Signals are used to notify a
process when an error that is not related to input or output has occurred. See also Open System
Services (OSS) signal, TNS signal, TNS/R native signal, and TNS/E native signal.
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