glossary

A pathname that begins with the root directory, such as /SYS/PUB/TDP. See also pathname and relative pathname.

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.

A type of access permitted to a file, such as write, read, or execute access.

Having sufficient capabilities to perform an operation on MPE/iX. SM capability always provides appropriate privilege to system administrators.

Storing infrequently used or out-of-date files onto tape and permanently removing them from the system disks at the same time.

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.

The process that duplicates computer data to offline media, such as a magnetic tape. Backups protect data if a system problem should occur.

System peripherals that allow you to write information to, and read information from, backup media.

HFS filenames can be saved in uppercase or lowercase letters. The file named ./FILE1 does not refer to the same file as ./file1 or ./File1.

A letter, number , or symbol represented by one byte of data.

A series of characters to substitute for a single character to name a group of files.

A system-reserved word that directs the operating system, a subsystem, or a utility program to perform a specific operation.

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.

A set of multiple, concurrently accessible backup devices to which you are able to store information simultaneously.

A set of multiple backup devices used for a given tapeset to which you are able to store information sequentially.

See system console.

The directory in which you are working and from which relative pathnames are resolved. See also directory and relative pathname.

Digital Audio Tape. A data storage media used by the HP 1300H DDS-format device.

The use of data compression algorithms on the host system to reduce the amount of data transferred to the output device.

An integrated collection of logically related data files and the structural information about the data.

Digital Data Storage. A format for storing computer data on DAT cassettes.

See peripheral.

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.

A series of identical backup devices.

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.

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.

A circular plate of magnetically coated material used to store computer data. A disk may be fixed, removable, hard, or flexible.

Convention that signifies the current working directory in HFS syntax. See also current working directory and HFS syntax.

Convention that signifies the parent directory in HFS syntax. See also current working directory and HFS syntax.

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.

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).

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 filename so that the user can access the file's contents.

A method of equating a filename 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.

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.

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 filename length and the characters that can compose the name. See also MPE syntax and HFS syntax.

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.

A number that determines group access privileges. (On MPE/iX, it is actually the string @.account).

A system database that contains the group name, group ID, and user names for all groups.

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:

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.

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.

A text file containing the parameters for a STORE or RESTORE command that you execute regularly.

The data to be processed, or the process of transferring data from external storage to the computer.

The process of, or equipment used in, transmitting information to or from the computer.

A method of writing data to a disk device for the purpose of improving data access speed.

A single file, submitted by a user, containing operating system and utility commands and references to the files to be manipulated.

Devices capable of storing data, such as disks or magnetic tape.

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.

The name of the surface within the media set to use. The media sub-name is the sub-name assigned during the STORE operation.

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.

Rules that determine the filename length, special characters, and conditions for files, groups, and accounts. Account, group, and filenames 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).

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.

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 means that the STORE fileset and structures are accessible for any access while the backup is taking place. Any modifications made to the STORE fileset 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.

Data transferred from internal to secondary (external) storage in a computer. Also, the process of transferring information from the computer to a peripheral device.

A set of backup devices to which you are able to store information simultaneously.

A value in a list of values that is passed to a procedure. The parameter is used on calculations or operations in the procedure.

A directory that contains other directories.

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.

A hardware device attached to and controlled by a computer, such as a terminal, a tape or disk drive, or a printer.

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.

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.

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.

A parameter that is required when entering a command or calling an intrinsic. In reference manuals, required parameters are surrounded by braces ({}).

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.

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.

Used tapes containing information that is no longer needed.

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.

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.

Another name for the root directory. See also root directory.

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.

A directory that is contained within another directory is sometimes referred to as a subdirectory.

The point in time the backup occurs, where all files are synchronized. It can occur at different times, depending on the type of backup performed. You can schedule when the sync point occurs by scheduling when the backup job is launched.

A group of one or more CPUs that communicate through buses without the use of data communications software.

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.

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.

The person who manages the computer installation, responsible for creating accounts and assigning capabilities and resource-use limits to each.

A printed message at the console asking for a backup device to be assigned to a user.

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.

A tool that allows users to perform application and system backups without closing files or disrupting users.

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.

An operating system program that performs specific functions such as file copying, sorting and merging, memory dump analysis, or monitoring available disk space.

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 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.

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.

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.

A plastic ring that fits onto the inner groove of a reel-to-reel tape, enabling you to write information onto the tape.

To remove a disk's write-protection, allowing the disk to be written upon.

To protect stored data so that it cannot be overwritten.