NonStop S-Series Hardware Installation and FastPath Guide (G06.25+)
Glossary
HP NonStop S-Series Hardware Installation and FastPath Guide—529443-001
Glossary-73
open migration
is associated with only one open file but can be associated with one or more file 
descriptors.
open migration. In the Open System Services (OSS) file system, the set of events and 
outcomes that occur when an open file description is inherited by a child process in a 
different processor than its parent process. Contrast with open propagation.
open propagation. In the Open System Services (OSS) file system, the set of events and 
outcomes that occur when an open file description is inherited by a child process in the 
same processor as its parent process. Contrast with open migration.
Open SCSI. A subsystem that provides the hardware and software for a SCSI-2 open 
interface that runs on HP NonStop™ S-series servers and to which developers can 
attach small computer system interface (SCSI) devices.
open system. A system with interfaces that conform to international computing standards 
and therefore appear the same regardless of the system’s manufacturer. For example, 
the Open System Services (OSS) environment on HP NonStop™ systems conforms to 
international standards such as ISO/IEC IS 9945-1:1990 (ANSI/IEEE Std. 1003.1-
1990, also known as POSIX.1), national standards such as FIPS 151-2, and portions 
of industry specifications such as the X/Open Portability Guide Version 4 (XPG4).
Open System Services (OSS). An open system environment available for interactive or 
programmatic use with the HP NonStop™ operating system. Processes that run in the 
OSS environment usually use the OSS application program interface. Interactive users 
of the OSS environment usually use the OSS shell for their command interpreter. 
Synonymous with Open System Services (OSS) environment. Contrast with Guardian.
Open System Services (OSS) environment. The HP NonStop™ Open System Services 
(OSS) application program interface (API), tools, and utilities. 
Open System Services (OSS) Monitor. A Guardian utility that accepts commands affecting 
OSS objects through an interactive Guardian interface named the Subsystem Control 
Facility (SCF).
Open System Services (OSS) signal. A signal model defined in the POSIX.1 specification 
and available to processes in the OSS environment. OSS signals can be sent between 
processes.
Open Systems Interconnection (OSI). A seven-layer network architecture model defined 
by the International Organization for Standardization (ISO). The two lowest layers deal 
with the physical connections and their protocols. The five upper layers deal with 
network services, such as network file transfers and access to remote databases.










