MPE/iX Glossary of Terms and Acronyms (32650-90887)

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Glossary of Terms
for a given file.
external interrupt message (EIM) A mechanism used by a module to signal to the
processor that the module has completed a requested operation and is
ready for another.
extra data segment capability (DS capability) A capability assigned by the system
manager to users and accounts to use extra data segments. DS capability
is normally restricted to only a few users, since allowing many processes to
use extra data segments can easily overload the system, requiring large
amounts of main memory, a large virtual storage area on the system disk,
frequent disk swapping, or all three.
Facility/Link An MPE communications subsystem. It allows users to access a
mainframe computer in interactive mode using a Hewlett-Packard
distributed systems network (DSN). It is usually known as Interactive
Mainframe Facility/Link.
FCOPY An HP 3000 subsystem that allows the user to copy, append, translate
data from one type to another (for example, ASCII to EBCDIC), verify, and
compare files. The subsystem is activated with the MPE/iX FCOPY
command.
fiber optics The technology of transmitting data over communication lines made from
flexible strands of glass or plastic through which laser beams or light from
light emitting diodes are passed to transfer data. The strands are formed
into cables and can carry many more times the amount of data than
traditional copper wire.
field replaceable unit (FRU) An assembly that is replaced when any of its components
fail.
file A group of related records that represents ASCII text (text files) or binary
data (such as executable code). Every file must have a file name so the user
can access the file's contents.
file access permission The determination whether a process may perform a requested
operation on a file. Every file in the file system has a set of access
permissions. These permissions are broken down according to whether a
file may be read, written, or executed.
file code A four-digit integer that identifies the special function of a file. Users may
assign a file code between 0 and 1023 to a file they create to classify it
according to its purpose.
file creation time The time when a file is created.
file directory A directory maintained by the system containing each file's name, who
created it, its location, and other defining characteristics.
file equation A method of equating a name with a specific device or file. This name
serves as an "alias" for another device or file whose characteristics are
defined in the file equation. The MPE/iX FILE command is used to define
the file equation. File equations are often used to direct the input to or
output from a program, job, or session to a particular device or file.