NonStop S-Series System Expansion and Reduction Guide

Glossary
G-Series Common Glossary
Glossary-35
field
field. In a structured programming language, an addressable entry within a data structure.
The term
field is sometimes used to mean member.
field-programmable gate array (FPGA). A programmable integrated circuit that can be
customized to perform specific functions.
field-replaceable unit (FRU). A unit that can be replaced in the field only by qualified
personnel trained by HP and cannot be replaced by customers. A unit is classified as a
FRU because of safety hazards such as weight, size, sharp edges, or electrical
potential; contractual agreements with suppliers; or national or international standards.
See also customer-replaceable unit (CRU)
.
FIFO. A type of Open System Services (OSS) special file that is always read and written in
a first-in, first-out manner.
FIFO special file. See FIFO.
file. An object to which data can be written or from which data can be read. A file has
attributes such as access permissions and a file type. In the Open System Services
(OSS) environment, file types include regular file, character special file, block special
file, FIFO, and directory. In the Guardian environment, file types include disk files,
processes, and subdevices.
file class. The property of an Open System Services (OSS) file indicating access
permissions for a process related to the owner, group, or other identification of the
process. See also file group class
, file other class, and file owner class.
file description. See open file description.
file descriptor. In the Open System Services (OSS) file system, the nonnegative integer
that uniquely identifies a single open of a file to a running process. Each file descriptor
is associated with an open file description that contains data about the file.
file group class. The property of an Open System Services (OSS) file indicating access
permissions for a process related to the group ID of the process. A process is in the file
group class of a file if both:
•
The process is not a member of the file owner class for the file.
•
The process has an effective group ID or supplementary group ID that is the same
as the group ID associated with the file.
file identifier. In the Guardian environment, the portion of a filename following the
subvolume name. In the Open System Services (OSS) environment, a file identifier is a
portion of the internal information used to identify a file in the OSS file system (an
inode number). The two identifiers are not comparable.
file link count. The total number of directory entries for an Open System Services (OSS)
file within an HP NonStop™ node.