Object Code Accelerator Manual

Glossary
Object Code Accelerator Manual—528144-003
Glossary-23
selectable segment
selectable segment. A type of logical segment formerly known as an extended data
segment. The data area for a selectable segment always begins with relative segment
4, and this area can be dynamically switched among several selectable segments by
calls to the Guardian SEGMENT_USE_ procedure. The effect is similar to a rapid
overlaying of one large data area. See also logical segment and flat segment.
sequence number. See process sequence number.
server. (1) An implementation of a system used as a stand-alone system or as a node in an
Expand network. (2) A combination of hardware and software designed to provide
services in response to requests received from clients across a network. For example,
HP NonStop™ servers provide transaction processing, database access, and other
services. (3) A process or program that provides services to a client or a requester.
Servers are designed to receive request messages from clients or requesters; perform
the desired operations, such as database inquiries or updates, security verifications,
numerical calculations, or data routing to other computer systems; and return reply
messages to the clients or requesters. A server process is a running instance of a
server program.
shared data segment. An extended data segment that can be accessed by more than one
process.
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). An object file that the operating system links to a program
file at run time. See also TNS/R native shared run-time library (TNS/R native SRL)
.
signal. A means by which a process can be notified of or affected by an event occurring in
the system. Some signals are used to notify a process when an error not related to
input or output has occurred. See also TNS/R native signal
and OSS signal. Contrast
with trap.
signal handler. A procedure that is executed when a signal is received by a process.
single-threaded process. A process that performs only one operation at a time. Contrast
with multithreaded process.
site update tape (SUT). One or more tapes that contain each target system’s site-specific
subvolume and various products. Each product contains a softdoc and a complete set
of files. A SUT is delivered with every new HP NonStop™ system and can be ordered
whenever a new release version update (RVU) of the system software is available. A