NBT Manual

Glossary
NBT Manual—424773-001
Glossary-14
noncritical event
noncritical event. A DSM event not too crucial to system or network operations. Each
subsystem determines which of its events are noncritical by setting the value of the
emphasis token to FALSE. Compare critical event.
nonsensitive command. A DSM command that can be issued by any user or program
allowed access to the target subsystem—that is, a command on which the subsystem
imposes no further security restrictions. For Compaq data communications subsystems,
the nonsensitive commands are all those that cannot change the state or configuration of
objects (usually information commands). Compare sensitive command
.
nowait mode. In Guardian file-system operations and in some APS operations, the mode in
which the called procedure initiates an I/O operation but does not wait for it to complete
before returning control to the caller. In order to make the called procedure wait for the
completion of the operation, the application calls a separate procedure. Compare wait
mode.
object. (1) In general Compaq use, one or more of the devices, lines, processes, and files in a
Compaq subsystem; any entity subject to independent reference or control by one or
more subsystems. (2) In DSM use, an entity subject to independent reference and control
by a subsystem: for example, the disk volume $DATA or the data communications line
$X2502. An object typically has a name and a type known to the controlling subsystem.
object-name template. In DSM, a name that stands for more than one object. Such a name
includes one or more wild-card characters, such as * and ?. See also wild-card character
.
object type. In DSM, the category of objects to which a specific object belongs: for example,
a specific disk file might have the object type FILE, and a specific terminal might have
the object type SU (subdevice). A subsystem identifies a set of object types by the
objects it manages. The SCF interfaces to Compaq data communications subsystems use
standard keywords to identify the types. The corresponding programmatic interfaces
have object-type numbers (represented by symbolic names such as ZCOM-OBJ-SU)
suitable for passing to the SPI SSINIT procedure.
open system. Any computer system that adheres to the OSI standards.
Open Systems Interconnection. A set of standards used for the interconnection of
heterogeneous computer systems, thus providing universal connectivity.
OSI. See Open Systems Interconnection
.
OSI Reference Model. A communications architecture, adopted by the ISO in 1984, that
includes seven layers that define the functions involved in communications between two
systems, the services required to perform these functions, and the protocols associated
with these services.
Outside View (OV). Compaq software product that includes several types of terminal
emulators that run on a PC with the Windows or OS/2 operating system. The Compaq
emulator in Outside View provides a 65xx connection and IXF file transfer to a Compaq
system.