Open System Services Management and Operations Guide (G06.30+, H06.08+, J06.03+)

See also Coordinated Universal Time (UTC).
Event Management
System
The product on NonStop systems that manages the events created by other products executing
on NonStop systems.
FIFO A type of file that is always read and written in a first-in, first-out manner.
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 OSS environment, file types include regular
file, character special file, FIFO, pipe, socket, symbolic link, Guardian file, and directory.
file privileges Additional privileges that can allow programs special access to files in restricted-access filesets
See also restricted-access fileset.
file system In the OSS environment, a collection of files and file attributes. A file system provides the
namespace for the file serial numbers that uniquely identify its files. Open System Services provides
a file system (see also ISO/IEC IS 9945-1: 1990 [ANSI/IEEE Std. 1003.1-1990], Clause
2.2.2.38); the Guardian application program interface (API) provides a file system; and OSS
Network File System (NFS) provides a file system. (OSS NFS filenames and pathnames are
governed by slightly different rules than OSS filenames and pathnames.) Within the OSS and
OSS NFS file systems, filesets exist as manageable objects.
On an HP NonStop system, the Guardian file system for a node is a subset of the OSS virtual
file system. Traditionally, the API for file access in the Guardian environment is referred to as the
“Guardian file system.”
In some UNIX and NFS implementations, the term “file system” is used to mean the same thing
as “fileset.” That is, a file system is a logical grouping of files that, except for the root of the file
system, can be contained only by directories within the file system.
See also fileset.
filename In the OSS environment, a component of a pathname containing any valid characters other than
a slash (/) or a null. In the Guardian environment, a filename is the set of node name, volume
name, subvolume name, and file identifier characters that uniquely identifies a file.
fileset In the OSS environment, a set of files with a common mount point within the file hierarchy. A
fileset can be part or all of a single virtual file system.
On an HP NonStop system, the Guardian file system for a node has a mount point and is a subset
of the OSS virtual file system. The entire Guardian file system therefore could be viewed as a
single fileset. However, each volume, and each process of subtype 30, within the Guardian file
system is actually a separate fileset.
The term “file system” is often used interchangeably with “fileset” in UNIX documentation.
fileset inode A fileset entity representing a file or directory.
free list The list of available inodes that can be allocated to files.
Guardian An environment available for interactive or programmatic use with the HP NonStop operating
system. Processes that run in the Guardian environment usually use the Guardian system procedure
calls as their application program interface; interactive users of the Guardian environment usually
use the HP Tandem Advanced Command Language (TACL) or another HP product’s command
interpreter. Contrast with Open System Services (OSS).
hard link The relationship between two directory entries for the same file. A hard link acts as an additional
pointer to a file. A hard link cannot be used to point to a file in another fileset. Contrast with
symbolic link.
inode A data structure that stores the location of a file.
large file aware An application or function that can process large OSS files in addition to small OSS files. For
example, it must be able to access large files as input and generate large files as output. Contrast
with large file safe.
large file safe An application or function that causes no loss of data or corruption of data when it encounters
a large OSS file. A large file safe application or function is not required to process large OSS
files with the same ability as when it processes small files, but it must handle errors or warnings
detected during file manipulation operations and fail gracefully. Contrast with large file aware.
large OSS file A regular file that has a size greater than or equal to approximately 2 gigabytes. Contrast with
small OSS file.
422 Glossary