HP 3000 Manuals HP 3000 Manuals
GLOSSARY
absolute pathname
A pathname that begins with the root directory, such as /SYS/PUB/TDP. See
also pathname and relative pathname.
access control definition (ACD)
Security feature that controls access to files and directories. Consists
of a list of access permissions and user specifications. (For example,
R,W,X:@.PAYROLL gives all users in the PAYROLL account read, write, and
execute access to the file or directory that is assigned this ACD.) ACDs
are applied to files or directories by using the ALTSEC command. By
default, all files existing outside the traditional MPE account/group
structure and all directories are assigned ACDs when they are created.
access mode
A type of access permitted to a file, such as write, read, or execute
access.
appropriate privilege
Having sufficient capabilities to perform an operation on MPE/iX.
SM capability always provides appropriate privilege to system
administrators.
archiving
Storing infrequently used or out-of-date files onto tape and permanently
removing them from the system disks at the same time.
back reference
The technique of using an asterisk (*) before a formal file designator to
indicate that it has been previously defined during the current session
or job with the FILE command.
backup
The process that duplicates computer data to offline media, such as a
magnetic tape. Backups protect data if a system problem should occur.
backup devices
System peripherals that allow you to write information to, and read
information from, backup media.
case sensitivity
HFS file names can be saved in uppercase or lowercase letters. The file
named ./FILE1 does not refer to the same file as ./file1 or ./File1.
character
A letter, number , or symbol represented by one byte of data.
character set
A series of characters to substitute for a single character to name a
group of files.
command
A system-reserved word that directs the operating system, a subsystem, or
a utility program to perform a specific operation.
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.
concurrent backup devices
A set of multiple, concurrently accessible backup devices to which you
are able to store information simultaneously.
consecutive backup devices
A set of multiple backup devices used for a given tapeset to which you
are able to store information sequentially.
console
See system console.
current working directory
The directory in which you are working and from which relative pathnames
are resolved. See also directory and relative pathname.
DAT
Digital Audio Tape. A data storage media used by the HP 1300H DDS-format
device.
database
An integrated collection of logically related data files and the
structural information about the data.
data compression
The use of data compression algorithms on the host system to reduce the
amount of data transferred to the output device.
DDS
Digital Data Storage. A format for storing computer data on DAT
cassettes.
device
See peripheral.
device class
A collection of devices that have some user-defined relation. The MPE/iX
file system supports a means of maintaining collections of devices but is
cognizant of the relation only for certain MPE device class names.
device pool
A series of identical backup devices.
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.
directory
A special kind of file that contains entries that point to other files.
It acts like a container for files and other directories. On MPE/iX,
accounts and groups are special types of directories.
disk
A circular plate of magnetically coated material used to store computer
data. A disk may be fixed, removable, hard, or flexible.
dot (.)
Convention that signifies the current working directory in HFS syntax.
See also current working directory and HFS syntax.
dot-dot (..)
Convention that signifies the parent directory in HFS syntax. See also
current working directory and HFS syntax.
dot-slash (./)
A convention that you can use to refer to a file using HFS syntax in your
current working directory. For example, ./myfile.old refers to the file
myfile.old in your current directory.
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).
file
An object that can be written to, read from, or both. A file has certain
attributes including access permissions and file type. 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 that the
user can access the file's contents.
file equation
A method of equating a file name to a device or another file. The MPE/iX
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 name
A name of a file that can be in MPE syntax (FILE.GRP.ACCT) or HFS syntax
(/ACCT/GRP/FILE1). Each syntax has different restrictions on file name
length and the characters that can compose the name. See also MPE syntax
and HFS syntax.
file owner
The person who has complete access to a file unless the user is
restricted by a $OWNER ACD entry. The $OWNER ACD entry can restrict the
file access of the file owner. The file owner is similar to the file
creator. The command LISTFILE filename -3 displays the fully qualified
user ID (user.account) of the file owner.
group
For POSIX compatibility, refers to a group of related users. This is
distinct from MPE groups, which are special types of directories existing
directly below accounts.
group ID database
A system database that contains the group name, group ID, and user names
for all groups.
group ID (GID)
A number that determines group access privileges. (On MPE/iX, it is
actually the string @.account).
HFS syntax
Expanded MPE/iX syntax that is case sensitive and allows users to address
multiple levels in the hierarchical file system. A name beginning with
"./" or "/" automatically signifies HFS syntax to MPE/iX.
Some additional rules are as follows:
* Names of directories directly under root or under an account may
have up to 16 characters.
* Names of directories or files not directly under the root or a
group can be up to 255 characters.
* Names of directories and files can contain the following special
characters: hyphen (-), dot (.), or slash (/)
hierarchical file system (HFS)
A file system that is tree structured and can contain files at many
different levels. This file organization is obtained through the use of
directories, which can contain files and other directories.
indirect file
A text file containing the parameters for a STORE or RESTORE command that
you execute regularly.
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.
interleave
A method of writing data to a disk device for the purpose of improving
data access speed.
I/O error
A data transmission error between a computer and peripheral. Examples of
I/O errors are baud rate or parity mismatch, and incorrect syntax in
device-control instructions.
job
A single file, submitted by a user, containing operating system and
utility commands and references to the files to be manipulated.
media
Devices capable of storing data, such as disks or magnetic tape.
media name
The name of the media set to make available for use by TurboSTORE/XL II.
The media name is the name assigned during the STORE operation.
media sub-name
The name of the surface within the media set to use. The media sub-name
is the sub-name assigned during the STORE operation.
mounting
The act of making a data storage device accessible. To physically mount
the device, you load the media onto the device. To logically mount the
device, you tell the operating system which device you want to use, and
it allows you access to that device.
MPE/iX
Multi-programming executive with intetrated Posix: The operating system
for 900 Series HP 3000 computers. MPE/iX manages all system resources
and coordinates the execution of all programs running on the system.
MPE syntax
Rules that determine the file name length, special characters, and
conditions for files, groups, and accounts. Account, group, and file
names can be up to 8 characters. Characters are always converted up
uppercase. Characters must be alphanumeric. This is the syntax current
MPE/iX users are used to using (for example, LEDGER.PUB.SYS).
native mode (NM)
The native run-time environment of MPE/iX. In native mode, source code
has been compiled into the native instruction set of the 900 Series HP
3000.
online backup
Online backup means that the STORE file set and structures are accessible
for any access while the backup is taking place. Any modifications made
to the STORE file set during the backup are logged and saved along with
the data on the backup medium. On RESTORE, the data and log file are
used to recover the data to a consistent state.
output
Data transferred from internal to secondary (external) storage in a
computer. Also, the process of transferring information from the
computer to a peripheral device.
parallel devices
A set of backup devices to which you are able to store information
simultaneously.
parameter
A value in a list of values that is passed to a procedure. The parameter
is used on calculations or operations in the procedure.
parent directory
A directory that contains other directories.
pathname
A way of identifying the path to any MPE/iX file. For example, you can
refer to FILE1.PUB.SYS using the pathname /SYS/PUB/FILE1. Notice that
pathnames are top- down rather than bottom-up as MPE syntax.
peripheral
A hardware device attached to and controlled by a computer, such as a
terminal, a tape or disk drive, or a printer.
POSIX
Portable Operating System Interface. A set of standards that address
various areas of operating system technology. The POSIX standards
describe functions of an operating system interface that applications use
to become "POSIX- compliant." The main point of POSIX is to facilitate
software portability and minimize porting costs.
purge
To delete a permanent file from the system with the PURGE command. The
PURGE command is also used to delete an account structure entry such as a
user name, a group name, or an account.
relative pathname
A pathname that is interpreted from the current working directory. For
example, ./dir1/longfilename refers to the file longfilename in directory
dir1 in the current working directory.
required parameter
A parameter that is required when entering a command or calling an
intrinsic. In reference manuals, required parameters are surrounded by
braces ({}).
restore
The process of retrieving user files from SYSGEN (MPE/iX), SYSDUMP (MPE
V/E), and STORE tapes or serial disk and writing them to disk. Restoring
is executed with the RESTORE command.
root directory
Also called (and designated by) a slash or /. It is a system directory;
all files, accounts, groups, and directories connect back to the root
directory. All accounts on MPE/iX are direct descendants of the root
directory.
scratch tapes
Used tapes containing information that is no longer needed.
sequential
A manner in which information may be read from or written to a device.
Sequentially accessed files are stored in such a way that the logical
order of the file's record is identical to their physical layout on disk
or tape.
shadow logging
A method of saving the "before" images of file blocks when the records in
the file block are modified during online backup. The before images are
stored on tape and are used by RESTORE to reconstruct the original
contents of the file.
slash (/)
Another name for the root directory. See also root directory.
storage device
A device (such as a disk pack, a disk cartridge, a flexible disk,
magnetic tape, or cartridge tape), onto which data can be stored and
subsequently retrieved.
subdirectory
A directory that is contained within another directory is sometimes
referred to as a subdirectory.
system
A group of one or more CPUs that communicate through buses without the
use of data communications software.
system console
1)A workstation given a unique status by the operating system. It is
used by the operator to execute specific commands for the purpose of
managing sessions, jobs, and system resources. It is associated with all
boot or system loader error messages, system error messages, and certain
system status messages.
2)The terminal, usually logical device 20, that the system operator uses
to monitor system activity, respond to resource requests, and send
messages to user's terminals. The console (and its associated privileges
and responsibilities) may be transferred to another logical device with
the CONSOLE command.
system file directory
A directory maintained by MPE that records the name, group, and account
of each permanent file on the system. The directory contains the size of
each file, its location on the disk, who may access it, and other
information.
system manager
The person who manages the computer installation, responsible for
creating accounts and assigning capabilities and resource-use limits to
each.
tape request
A printed message at the console asking for a backup device to be
assigned to a user.
transport backup
Transport refers to the movement of files between MPE V/E and MPE/iX
systems using backup media. MPE/iX backup and recovery provides a
compatibility option with which an MPE V/E-compatible tape may be created
or read.
user
Anyone logged on to a session, using a local or remote terminal to
interact with the computer. Each user is identified by a user and
account name, and can access files in the logon group.
utility program
An operating system program that performs specific functions such as file
copying, sorting and merging, memory dump analysis, or monitoring
available disk space.
volume
A volume is one disk. Each volume is a member of a volume set and
contains a volume label, a label table, and a free space map.
volume class
Volume classes are used for the allocation and restriction of disk space.
A volume class is a logical subset or partition within a volume set and
can bridge any number of physical member volumes of a volume set.
volume set
A volume set is a group of from 1 to 255 related disks. One volume of
the volume set must be designated as the master volume for the set. Each
volume set is assigned a name by which it is identified and referenced.
wildcard
A symbol that is used to replace a character or set of characters. In
MPE, the "at sign" (@), the "pound sign"(#), and the question mark (?)
are used as wildcard characters.
write-enable
To remove a disk's write-protection, allowing the disk to be written
upon.
write-protect
To protect stored data so that it cannot be overwritten.
write ring
A plastic ring that fits onto the inner groove of a reel-to-reel tape,
enabling you to write information onto the tape.