HP 3000 Manuals HP 3000 Manuals
Appendix C Glossary
abort A procedure that terminates a program or
session if an irrecoverable error, mistake,
or malfunction occurs.
access The process of obtaining data from files or
acquiring the use of a device. Access
implies an input/output (I/O) operation, and
is used as a synonym for I/O.
access port (AP) The MPE XL system console interfaces the
host system through the Access Port (AP)
located in the Channel I/O (CIO) section of
the system card cage. The AP provides a
user support interface for issuing hard and
soft resets through software commands from
the console. It allows a remote console to
be enabled and to switch between console and
session modes.
account A collection of users and groups. Each
account has a unique name on the system. It
is the method used to organize a system's
users and files and allocate use of system
resources such as central processor time,
online connect time, and file space.
Accounts are the principal billing entity
for the use of these resources. Every user
must specify an account to access the
system.
account level security The types of file access assigned by the
system manager to the account when it is
created. The types of access are APPEND,
WRITE, and EXECUTE, abbreviated R, L, A, W,
and X respectively. They may be assigned to
any user (ANY), members of the account only
(AC), or members of the group only (GU). The
types of file access permitted are the first
level of system security. The account
manager may further restrict groups and
users within an account by assigning them a
limited set of file access modes.
account librarian A capability assigned by the account manager
capability (AL Capability) to a user within the account. An account
librarian is allowed special file access
modes to maintain specified files within the
account.
account manager capability A capability assigned by the system manager
(AM capability) to one user within each account who is then
responsible for establishing users and
groups.
account member A person who has been granted access to the
system through the use of a valid user name
within an account. Account members are
created by the account manager, who defines
the user name and assigns the user
appropriate capabilities and security
restrictions.
account structure The account structure provides organization,
security, and billing for the system. It is
used to allocate use of system resources
such as central processor time, online
connect time, and file space. The account
is the principal billing entity for the use
of system resources.
ACTIVE state The status of either an input or output
spoolfile (defined differently for each).
During input spooling, an ACTIVE file is a
spoolfile being created, indicating that the
input spooler is still collecting data from
the input device. An ACTIVE output
spoolfile is the only file being output to a
device. For example, when the standard
output device is the system printer the file
being printed is ACTIVE.
actual file designator The file name provided by the user. The
system then uses the file name in place of
the formal file designator to accomplish
some task. The actual file designator is
the file name listed in the directory. See
formal file designator.
address 1) A number identifying an exact location in
memory. A process can send data to, or
retrieve data from, this address. 2) A set
of values identifying a specific peripheral
(I/O) device to the computer. The exact
details on the formation of an address
differ between systems.
advanced terminal processor An intelligent hardware interface between
(ATP) terminals and the HP 3000. The ATP handles
character processing and eliminates CPU
interrupts. It supports full-duplex
asynchronous modems and direct memory access
of user data.
allocate 1) To locate and reserve disk space for a
particular file. 2) To load a program into
memory with the ALLOCATE command. Such
programs remain in memory until unloaded
with the DEALLOCATE command, or until the
system is halted.
alpha character A character in the range of A through Z (or
a-z).
alphanumeric character A character in the range of A through Z (or
a-z), or 0 through 9.
alternate boot path The alternate boot path is used for booting
the system from a boot tape. See boot path.
American Standard Code for The standard method of representing
Information Interchange character data (seven data bits plus one
(ASCII, USASCII) that is sometimes used for parity). This
method was established by the American
National Standards Institute (ANSI) to
achieve compatibility between data devices
when they are interchanging information.
analog Data that varies continuously rather than in
discrete steps. When used in reference to
circuits, those circuits that produce an
output varying as an uninterrupted function
of the input. The opposite of digital.
application A set of computer instructions or programs
that guide the computer through a specific
task or set of tasks. Examples of
applications include spreadsheets, word
processing programs, graphics, database
management, and communications.
application engineer (AE) A Hewlett-Packard software engineer who can
tailor an operating system to meet the
customer's needs.
application program A set of computer instructions that guides
the computer through a specific set of
tasks. Applications include spreadsheets,
word processing, graphics, database
management, and data communication programs.
architecture 1) The unique set of machine instructions,
registers, and other components that provide
the conceptual basis of a computer. 2) In
networking, a structured modular
network design in which different data
communications tasks are assigned to
different layers or levels. See open system
interconnection.
arithmetic logic unit (ALU) The part of a system that performs
arithmetic and logic operations as part of
the Central Processing Unit (CPU). The CPU
may contain one or more arithmetic logic
units.
ASCII American Standard Code for Information
Interchange: ASCII is the standard method
of rrepresentiing character data (seven bits
plus one that can be used for parity). This
method was established by the American
National Standards Institute (ANSI) to
achieve compatibiity between data devices
when they are exchanging information.
associated device A device within a device class assigned to a
user with the ASSOCIATE command.
Thereafter, the associated user has Operator
control of the designated device until the
user logs off, gives up control of the
device, or until the Operator regains
control with the DISASSOCIATE command.
attribute Attributes include file access codes and
special capabilities. They enable the
computer to determine what functions it will
or will not allow a user, group, or account
to perform.
autoboot The process of automatically starting the
system.
backreference The technique of using an asterisk (*)
before a formal file designator to indicate
it has been previously defined with the FILE
command.
backup The process that duplicates computer data to
offline media, such as magnetic tape.
Backups protect data if a system problem
should occur.
batch processing A method of submitting a job for processing.
A job, which is submitted as a single
entity, can consist of multiple commands
such as program compilation and execution,
file manipulation, or utility functions.
Once submitted, no further interaction
between the user and the job is necessary.
batch access capability (BA A default capability. It is assigned to
Capability) accounts and users, allowing users to submit
batch jobs.
binary A method of representing numbers, alphabetic
characters, and symbols in digital
computers. Binary is a base two numbering
system that uses only two digits, 0's and
1's, to express numeric quantities.
binary coded decimal (BCD) A decimal notation in which individual
decimal digits are each represented by a
group of four bits.
binary synchronous A data link protocol, also referred to as
communications (BSC) BISYNC. A line control stations in a data
communications system.
blank password When an account, group, or user does not
have a password.
block A group of one or more logical records
transmitted to or from a file in a single
input/output operation. Programs executed
during session, using a terminal as the I/O
device, use different block sizes to
facilitate data entry and update.
blocked A state transition of a process when it
relinquishes the CPU.
blocked record A physical record that contains more than
one logical record. The opposite of
unblocked record.
blocking factor The number of logical records in each block.
block mode A terminal processing mode. It transmits
groups, or blocks of characters all at once,
instead of one character at a time.
capability A method for determining what commands
account members are allowed to execute.
Capabilities are assigned to accounts,
groups, and users to provide system security
and access to the operating system. Account
capabilities are assigned by the system
manager when the account is created. The
Account Manager then assigns capabilities to
groups and users within the account.
card cage The structure used to hold cards in their
proper place inside the computer. Card
cage and I/O Bay are sometimes used
interchangeably, although the latter usually
refers to the entire cabinet containing one
or more card cages used to store the cards
that control I/O devices.
character A letter, number, or symbol represented by
one byte of data.
command A system-reserved word that directs the
operating system, a subsystem, or utility
program to perform a specific operation.
command file 1) A file a user creates to execute multiple
commands. To execute commands or UDCs
referenced with the command file, enter the
command file name at the system prompt. 2)
A set of one or more SQL or ISQL commands in
a file that can be executed with the ISQL
START command.
command interpreter (CI) CI: A program that reads command lines
entered at the standard input device,
interprets them, determines if they are
valid, and if so, executes them.
compatibility The ability of software developed for one
computer to work on another computer. See
compatibility mode.
compatibility mode (CM) Compatibility Mode provides object code
compatibility between MPE V/E-based systems
and the 900 Series HP 3000. Compatibility
mode allows current Hewlett-Packard
customers to move applications and data to
the 900 Series HP 3000 without changes or
recompilation.
computer A device that accepts information, processes
it, and supplies an output. A computer
usually contains memory, a control unit,
arithmetic and logical manipulators, and a
means for input and output.
configuration 1) The way in which computer and peripheral
devices are programmed to interact with each
other. 2) The layout of the computer
system, including MPE table, memory, and
buffer sizes. The configuration tells which
peripheral devices are connected to the
computer and how they can be accessed.
The system is configured by the
system supervisor, who works with the
Hewlett-Packard applications engineer (AE).
connect time The amount of time, in minutes, that a user,
group, or account has used the CPU for a
session or job. It is determined by
executing the MPE REPORT command.
console A terminal given unique status by the
operating system. The operator uses the
console to monitor and manage jobs, sessions
and resources, respond to requests, and
communicate with other user terminals. It
is used to boot the system and receive
system loader error messages, system error
messages, and system status messages.
console boot path Used to determine if the system can autoboot
without operator intervention. See boot
path.
console command A command that is executable only from the
System Console at the = prompt (generated by
pressing CTRL and the A key on the Console
keyboard). Console commands cannot be
distributed to MPE users, since CTRL A has
no meaning on a standard terminal. The
logical console, however, can be moved to a
standard terminal.
console logging A system logging event. It records console
commands in the system log file.
console message A message sent to the system console by the
system, an application, or a user.
continuation character An ampersand (&) character entered as the
last character of a command line. A
continuation character tells the command
interpreter that the command is longer than
one line and is continuing onto a second or
more subsequent lines.
control character A member of a character set that produces
action in a device rather than printing or
displaying a character. In the ASCII
character set, control characters are those
in the range 0 through 31, and 127. Control
characters are generated by pressing the
CTRL key and a character key simultaneously
(for example D). In documentation these
two-key sequences are shown as CTRL D or
D^^c^^.
control codes Special codes contained in data sent to a
peripheral device. These codes control how
the device operates.
control program The program responsible for handling I/O for
terminals and file storage, establishing
processing priorities, maintaining waiting
lists of work in process, activating
operational programs, and performing other
supervisory functions in a real time system.
Other terms used synonymously to designate
such a program are driver, executive,
monitor, kernel, and supervisor.
control unit A part of the CPU that regulates the
execution unit and oversees the instruction
cycle.
control-Y A break function activated by simultaneously
pressing the CTRL key and the Y key on a
terminal's keyboard. It is typically a
subsystem break and will not affect MPE
commands. In documentation this two-key
sequence is shown as CTRL Y or Y^^c^^.
CPU time The amount of time, in seconds, that a user,
group, or account has used the CPU. It is
determined by executing the MPE REPORT
command.
cursor 1) A flashing rectangle or blinking
underline character on a display screen. It
marks the position where text or data can be
entered, changed, or deleted. 2) In HP SQL,
the pointer to one tuple in a set of tuples
from an application program.
custom performance Using an outside performance expert to
consulting locate and evaluate performance problems.
customer engineer (CE) A Hewlett-Packard field representative
responsible for the installation,
troubleshooting, and maintenance of computer
hardware and operating systems.
database A collection of logically related data and
structural information about the data.
database management system A software package designed to protect the
(DBMS) consistency and security of data in
computer-stored files (databases). It
allows a user to define a database structure
and manipulate the contents by storing,
retrieving, deleting, modifying, and sorting
data.
data cache A high speed CPU cache implemented on the
900 Series HP 3000. It operates in parallel
with the instruction cache. Data is
transferred by load and store instructions
between the general purpose registers of the
execution unit and the data cache. It is a
write-to cache so the main memory modules
are updated only as required. See
instruction cache.
data communications The transmission of information from one
computer or terminal to another. It is
sometimes shortened to datacomm.
debug 1) To find and correct mistakes in a
computer program.
2) Debug/XL is the debug facility supplied
with MPE XL. It provides debug information
at the machine instruction (object code)
level. It can be used to debug programs
written in any Hewlett-Packard-supported
language, both in native mode and
compatibility mode.
decimal code The decimal representation of an ASCII
character. For example, the character A has
the ASCII binary code value 01000001 and the
decimal code value 65.
default A predefined value or condition that is
assumed, and used by the operating system if
no other value or condition is specified.
delimiter A special character used to mark the end of
a string of characters. Common delimiters
are a comma (,), semicolon (;), equal sign
(=), or a Return.
destructive testing A deliberate attempt to cause the system or
program to fail by including a test
specifically designed for that purpose.
device See peripheral.
device adapter A device that manages communications between
the computer and a peripheral device. It is
the same as an I/O interface card.
device class A collection of devices that have some
user-defined relation. The MPE XL File
System supports a means of maintaining
collections of devices but is cognizant of
the relation only for certain MPE device
class names.
device file A file associated with a non-shareable
device (a spoolfile). Input and output
spoolfiles are identified by a number in the
DFID (device file identification) column of
the SHOWIN and SHOWOUT command displays. A
device file may also refer to any non-disk
device, such as $STDIN and $STDLIST, the
default input and output device files for a
terminal.
device independence A characteristic of the operating system
that allows users to selectively redirect
input/output from a program, session, or job
without regard to the nature of the device
with the FILE command. File equations
created with the FILE command are in effect
only for the duration of the job or session
in which they were defined.
device reference table A table containing the logical address of
(DRT) disks, tape drives, and other peripheral
devices.
device subtype A number ranging from 0 to 15, defining a
specific device and its associated software
driver. There can be several device
subtypes within one basic type. For
example, a graphics terminal and one without
graphics capabilities can share the same
device type, but are assigned different
subtype numbers.
device type Device types are defined by a number. For
example, 0 represents a moving-head disk and
16 is the class type number assigned to line
printers.
Diagnostician Capability A capability usually assigned only to the
(DI Capability) Hewlett-Packard customer engineer (CE). It
allows the CE to conduct certain CPU and
diagnostic tests.
direct access To read from or write to a random access
device (usually a disk) by addressing a
specific logical record. Direct record
access is not possible on serial storage
media (such as magnetic tapes) since data
can only be read sequentially from the first
record (or byte) to the nth record (or
byte).
directory A system table showing in what group or
account each file is located. A directory
may contain other information such as size
of the file, its creation date, any
modification dates, file creator, or file
security information.
DISCFREE An MPE XL utility supplying information
about a system's disk free space, transient
and permanent space, and the volumes total
space capacity. The information is supplied
in either a histogram or a condensed format.
Equivalent to the MPE V/E FREE5 utility.
disk A circular plate of magnetically coated
material used to store computer data. A
disk may be fixed, removable, hard, or
flexible.
disk drive A peripheral device that reads information
from and writes information to the disk.
disk file A file stored on disk.
disk I/O is the electromechical process of
transferring the code and data that are
stored on disk into main memory.
disk pack A set of one or more disk platters stacked
inside a plastic cylindrical container.
disk platter An aluminum disk coated with magnetic
material. One or more platters are mounted
on a central spindle, and together they form
a complete disk pack. Information may be
recorded on one or both sides of each
platter within the pack.
disk sector A section of a disk's surface. A file is
stored in one or more sectors.
disk swapping The method used to manage the transfer of
programs and data files into and out of main
memory. Processes waiting for a system
resource to be available are swapped out to
an area on disk called virtual memory.
Another process, has the resources it needs
to execute, is swapped from virtual memory
into main memory, where it begins
processing. Disk swapping is handled
entirely by the operating system.
Distributed Systems Line The communications line between two
(DS Line)
computers, controlled by the Distributed
Systems Network.
Distributed Systems Network A system of hardware and software data
(DSN) communications products spanning multiple
Hewlett-Packard product lines.
Distributed Terminal An MPE XL intelligent controller, with
Controller (DTC) microprocessors to handle workstation
connection preprocessing, and another
microprocessor that handles communications
with the system.
DRT number Device Reference Table Number. The physical
I/O address of a device controller,
displayed in the second column of the I/O
Configuration Table listed during the
SYSDUMP dialog. An MPE V/E index into the
DRT.
duplex The method of transmission that allows
simultaneous two- way communication. Duplex
is usually called full-duplex. The opposite
of Half-Duplex.
echo To display data being typed on the keyboard
on the terminal screen. If echo is turned
off, the computer receives the data but
nothing appears on the screen.
editor A word processing application used to
prepare, modify, or delete text and program
files. EDIT/3000 is the text editor used
with MPE.
End of File (EOF) The marker that indicates the logical end of
a file. An end-of-file marker may be a
control character embedded in the data.
End of Line (EOL) The mechanism for indicating the end of a
line.
End of Tape (EOT) A marker on the back of a tape, sensed by
the tape drive, indicating the supply of
tape is running low.
environment file A compiled disk file containing the
specifications for a printed page of data.
These specifications, which are not part of
the data, may include the page size,
character fonts, forms, and other
requirements to be used in conjunction with
the HP Laser Printing System.
error listing A report generated by the system describing
the step by step processing of the job.
error messages Messages describing errors occurring during
either an interactive session or a batch
job. The messages are reported to the
standard list device, which is usually a
terminal (for a session) or a line printer
(for a job).
escape key A special terminal key, labeled ESC, that is
used in combination with other characters to
modify a session or terminal. It is
represented by ESC or Escape.
escape sequences A sequence of characters beginning with the
escape character and used to control
printers, plotters, or the display screen.
EXCLUSIVE access A restriction limiting file access to one
user t a time. EXCLUSIVE access is
particularly important during file updates,
when two or more people modifying the same
record within a file, at the same time,
could destroy data consistency.
execute When a command is entered, the computer
carries out the instructions or performs the
routine indicated.
executing state The state of a job/session, displayed when
the SHOWJOB command is executed. Possible
states are INTRO, WAIT, EXEC*, EXEC, and
SUSP.
Extended Binary-Coded An 8-bit code that is an extension of
Decimal Interchange Code Binary-Coded Decimal (BCD) notation. EBCDIC
(EBCDIC) can represent up to 256 different
characters.
extent A group of one or more contiguous sectors on
a volume used to allocate permanent disk
space. Extents can be variable length; any
number of extents can exist for a given
file.
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 XL FCOPY command.
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 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 directory A catalog 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 file name to a device
or another file. The MPE XL FILE command is
used to establish the relationship of the
file to the device. Generally used to
direct the input to or output from a
program, job, or session to a particular
device by referencing the device class, such
as TAPE or LP.
file identifier A number associating a name with a file
system object. The file identifier is given
to users to access objects via the file
system.
file independence File independence means that data files are
shareable among all the Hewlett-Packard
programming languages. For instance, an HP
Pascal/XL program can read files created
using any of the other supported programming
languages.
file label A descriptive entry on disk containing the
file name, file code, record size, file
format, current end-of-file mark, maximum
number of records, blocking factor, number
of disk sectors in use, number of extents
currently allocated, and maximum number of
extents. Use the LISTF,2 command to display
the file label.
file mark A uniquely formatted area on a magnetic tape
used to separate files. Also referred to as
a tape mark.
file name An MPE XL file name is a string of up to
eight alphanumeric characters, the first of
which must be an alphabetic character. The
file name is assigned when the file is
created or first saved.
file number An integer value assigned by the FOPEN
intrinsic that is used to refer to a file in
a user program. File numbers zero through
seven are reserved for the MPE XL operating
system.
file pointer A logical record pointer kept by the
operating system to indicate the next
sequential record to be accessed in a file.
The pointer is set to the first record when
the file is opened.
file space The number of sectors of disk space that a
user, group, or account is using. It is
determined by executing the MPE REPORT
command.
file specification The name and location of a file. The full
specification for a file includes the file
name, group, and account.
file state The condition of a spooled file; either
OPEN, READY, ACTIVE, or LOCKED. An OPEN
file, for example, is one currently being
accessed by a user or a program.
file system The part of the operating system that
handles access to input/output devices, data
blocking, buffering, data transfers, and
deblocking.
firmware A set of software instructions that cannot
be altered. Instructions are permanently
stored in READ-Only Memory (ROM) or
Writeable Control Store (WCS).
fixed disk A large capacity disk that is fixed inside a
disk drive. Unlike flexible disks, a fixed
disk cannot be removed.
fixed-length record A record that always contains the same
number of characters or words. Fixed-length
records within a single file are always the
same length.
flexible disk A random access storage device, also called
a diskette or floppy disk. Data may be
written to or read from one or both sides
with a special disk drive intended only for
diskettes. Flexible disks are often used
with personal computers.
formal file designator An alias file name that is used either
programmatically or in a file equation to
reference a file. The formal file
designator is not the file name found in the
system file directory.
formatting 1) To prepare a disk or tape so that files
may be written to it. 2) To prepare a file
to be output with a certain organization.
Formatting includes such processes as
setting page length and width, specifying
printing fonts, and adding headers and
footers.
free space map A map of allocated and available disk
sectors on the
fully qualified file name A complete file description that includes
the file name, the group to which the file
belongs, and the account to which the the
group belongs. The fully qualified file
name of the LETTER file in the PUB group of
the SYS account is expressed as
LETTER.PUB.SYS.
function keys Special keys on the terminal keyboard that
are labelled sequentially, F1, F2, F3, and
correspond to the windows that appear at the
bottom of the terminal screen. Function
keys perform various activities.
Fundamental Operating The programs, utilities, and subsystems
Software (FOS) supplied on the Master Installation Tape
(MIT) for MPE.
group A group is part of an account that is used
to organize the account's files. All files
must be assigned to a group, and within an
account each group has a unique name.
Groups are the smallest entity for which use
of system resources is reported. A PUB
group is designated for each account when it
is created. Additional groups are created
within the account, as needed, by the
account manager.
group-level security The file access modes, and the types of
users to whom they are available, as
specified by the account manager when the
group is created. File access modes
assigned to a group are limited to those
types permitted to the account.
group librarian capability GL capability: Assigned by the account
manager, to a user within an account. A
group librarian is allowed special file
access modes for the maintenance of certain
files within the user's home group.
hard copy The output from a printer or plotter,
usually onto paper. The opposite of soft
copy.
hard disk A device used to store information. A hard
disk has more storage than a floppy disk
without being susceptible to the same
hazards (for example, being bent or having
the media corrupted by physical handling).
hard reset A method to reset the computer or a
terminal. A hard reset erases all
information in memory. be See soft reset.
hardware All the physical components of the computer,
including the CPU cabinet, tape drives, disk
drives, terminals, and other peripherals.
hard-wired In a hard-wired computer, the instruction
set is implemented directly in the CPU.
hard-wired direct A direct connection between a computer and a
connection terminal or between two computers over a
relatively short distance using copper wire
pairs, coaxial cable, or fiber optics. The
signals are transmitted in digital format.
hard-wired terminal A terminal directly connected to the
computer system by a length of cable.
head The physical mechanism on a disk or
tapedrive that reads data from, and writes
data to, the disk or tape volume. The head
on a disk drive does not normally make
physical contact with the surface of the
media, but the tape head does.
header The first page printed when output is
directed to a line printer. It contains the
session name (if designated), the session
number, logon identification, day of the
week, date, and time. It corresponds to the
trailer printed as the last page of the
output.
HELP facility An online utility providing information on
all MPE commands. Information can be
accessed by topic areas and tasks.
Hewlett-Packard (HP) A Fortune 500 company founded by Bill
Hewlett and Dave Packard in 1939.
Hewlett-Packard is a producer of computers
and headquarters is located in Palo Alto,
California, U.S.A.
Hewlett-Packard Interface The HP-IB channel consists of an HP-IB cable
Bus (HP-IB) connected to an HP-IB interface card which
is connected to the system's backplane. It
performs protocol translation between the
CPU and HP-IB. For the 900 Series HP 3000 up
to six devices can be connected to a single
HP-IB channel. Disk drives, tape drives,
and system printers are connected via an
HP-IB which is HP's implementation of the
IEEE standard 488-1975 interface.
home directory The default group, within an account, used
as the current working directory when none
is specified at logon time.
home group A home group may be assigned to each user.
If no other group is specified with the
HELLO or JOB command, users are logged onto
their home group by default. If no home
group is assigned, the user must always
specify a group when logging on. The
account manager assigns the home group when
a user's name is first defined.
INITIAL An MPE V/E standalone program, executed
during a coldload, that loads the MPE
operating system, recovers spoolfiles,
handles disk errors, and reconfigures
input/output devices and system parameters.
Also called MPE Initiator, or the Initiator
Dialog. MPE XL equivalent is the SYStem
GENerator (SYSGEN) utility program.
input The data to be processed, or the process of
transferring data from external storage to
the computer.
input/output (I/O) The process of, or equipment used in,
transmitting information to or from the
computer.
input priority A number in the range of 1 (lowest priority)
to 14 (highest priority) assigned to input
jobs. The input priority can be assigned by
the system (default is 8) or by the user.
Jobs with a input priority less than or
equal to the system outfence (default 7) are
deferred.
interactive An interactive session allows users to enter
commands and data at the terminal and
receive an immediate response. Sessions are
useful for data entry and retrieval, text
editing, or program development where direct
dialog with the computer is preferred.
interactive access A capability assigned to accounts and users
capability (IA capability)
allowing users to initiate sessions with the
HELLO command.
interface The connecting circuitry linking the central
processor of a computer system to its
peripheral devices, or standards which allow
systems to connect to each other (for
example, RS- 232-C).
International Standards An organization established to promote the
Organization (ISO) development of standards and to facilitate
the international exchange of goods and
services. ISO created the Open Systems
Interconnection (OSI), a seven-layer
approach to network architecture.
interrupt A signal from a process or device to another
to immediately indicate that the sender's
status has changed. When a process is
interrupted, its processor status word (PSW)
is saved and the process suspended. The
interrupting process executes; then the
first process is reactivated and begins
processing from the point at which it was
interrupted.
intrinsic A system routine accessible by user programs
providing interface to operating system
resources and functions. Intrinsics perform
common tasks such as file access, message
formatting, or data conversion.
job A job is a method of submitting multiple
operating system and utility commands for
processing with a single command. Once
submitted, the job executes independently of
the user's session. Jobs are used to
compile source programs, modify files, or
perform other functions not requiring user
interaction. See also batch processing and
stream.
Job Control Word (JCW) A 32-bit logical word (16-bit for MPE V/E)
residing in an MPE-managed table, used to
pass information between processes. There
are system-defined and user-defined JCWs.
JCWs are used by jobs and sessions.
jobfence A limit established to manage jobs. If a
job has an input priority higher than the
jobfence, it will execute. If it has an
input less than or equal to the jobfence, it
will not execute.
job file A job file is used to define a job to the
system. It must start with a JOB command
and end with an EOJ command.