All important terms used in this manual are listed and defined in alphabetical order in this glossary. For terms specific to operating systems, the environment from which they are taken is specified (BS2000, POSIX or UNIX). Cross-references to other terms are given in italics.
64-bit file interfaces
Set of new file interfaces with which large POSIX files can be processed. These file interfaces have been derived from existing file interfaces and have the suffix 64, e.g. open64().
64-bit integer arithmetic
64-bit integer arithmetic uses integers which are 64 bits in length (without sign) or 63 bits and a sign bit. It is implemented using a pair of 32-bit integers (data type long long).
absolute path name
POSIX/UNIX: Path name which begins at the root directory (/) of the POSIX file system and leads through all superordinate directories to a specific file or directory. Every file and directory has a unique absolute path name.
access permission
POSIX/UNIX: Property of a file which controls access to this file. Access permissions are assigned separately to the owner (see file owner class), the owner group (see user class group), and all other users (see file group class). There are three basic access permissions: read, write and execute permission.
account number
BS2000: Refers to an account for the associated user ID. The same account number can be assigned to two or more user IDs. A user ID can have a maximum of 60 account numbers. The account number is evaluated for SET-LOGON-PARAMETERS and ENTER-JOB.
Application Programming Interface (API)
Interface between the applications and the system and subsystem functions they use.
ASCII
Abbreviation for American Standard Code for Information Interchange.
Standardized code for the conversion of uppercase and lowercase letters, digits, special and control characters into digital numbers which can be processed in the computer. UNIX and SINIX work with the ASCII code. POSIX can process ASCII data after it has been converted to EBCDIC format.
authentication
BS2000: Check of the user specifications during system access. The user attributes “User ID” and “Password” are checked against the entries in the user ID catalog.
background process
Process which does not completely exhaust the resources of the computer, but which facilitates the simultaneous execution of other processes. A background process normally utilizes the time slots during which the processor is less active.
block-mode terminal
Terminal which does not support character-by-character input and output operations.
bs2fs file system
Selectable set of files in BS2000 which are made available in POSIX as a file system, thus enabling them to be accessed using POSIX means (commands, program interfaces). The files are selected using the user and catalog IDs and wildcard symbols.
catalog identification, catid
BS2000: Identifier of a pubset.
The catalog identifier consists of a maximum of 4 characters, which within file names or path names must be enclosed in inverted commas. The catalog identifier is a component of the path name of a file.
child process
See fork
container file
POSIX: BS2000 PAM file in which a POSIX file system is stored. A container file is stored on a pubset. Container files and BS2000 files may be located on the same pubset.
current directory
POSIX/UNIX: Directory in which the user is currently working. It can be displayed by means of the POSIX command pwd. In the current directory, the user can access all files and subdirectories directly.
daemon
POSIX/UNIX: System process which runs permanently and usually in the background and performs general functions. The best-known example is the printer daemon, which ensures that a file is printed while the user continues to work.
directory
POSIX/UNIX: A directory is used to group and organize files or directories.
EBCDIC
Abbreviation for Extended Binary Coded Decimal Interchange Code.
EBCDI code is an 8-bit extended BCD code which is used on BS2000 computers, TRANSDATA communication computers and industrial standard machines.
file
UNIX: A file is identified in UNIX via an index entry. This entry contains information as to whether the file is a normal file, a special file or a directory. A normal file contains text, data, programs or other information. A special file refers to a device or part of a device, such as a drive or a hard disk partition for example. A directory contains other files.
BS2000: Records related to each other are combined in a named unit, the file.
Examples of files are conventional I/O program data, load modules, and text information which is created and processed with a file editor.
file group class
POSIX/UNIX: A process belongs to the file group class if it does not belong to the file owner class, and if the effective group number, or one of the additional group numbers of the process matches the group number of the files.
file other class
POSIX/UNIX: Property of a file which displays the access permissions of a process which is associated with the user ID of a process. A process belongs to the file other class of a file if it does not belong to the file owner class or the file group class.
file owner class
POSIX/UNIX: Property of a file which displays the access permissions of a process which is associated with the user and group identification of a process. A process belongs to the file owner class of a file, if the effective user number of the process matches the user number of the file.
file system
POSIX/UNIX: Collection of directories and files and specific file attributes.
first start
BS2000: The system files are created following first start of BS2000. The system assigns a range of user IDs, e.g. TSOS, SYSPRIV and SYSHSMS. The user ID catalog is always created in the course of a first start.
foreground process
Process which completely monopolizes the computer capacity, so that it cannot be used by other processes.
fork
POSIX/UNIX: System call which divides a process into two parts, the parent process and the child process.
group member
BS2000: User ID assigned to a user group. The group administrator can assign resources to a group member.
group ID
Non-negative whole number for identifying a group of users. Each user is a member of at least one group.
Large POSIX files
POSIX files which may be larger than 2 gigabytes (2 gigabyte = 231 -1 bytes). 64-bit arithmetic is required for addressing within a file of this size. Large POSIX files can only be created in large POSIX file systems and must be processed with 64-bit file interfaces.
Large POSIX file systems
POSIX file systems which can be larger than 2 gigabytes. 64-bit arithmetic is required for addressing within a file system of this size. The maximum size of a large POSIX file system is 1024 Gbyte. Large POSIX file systems are a prerequisite for large POSIX files.
home directory
POSIX: Directory into which the user is automatically placed when he/she connects with POSIX.
host
Central computer of a computer network. Programs are run, files are stored, and I/O is controlled on the host. A powerful computer network often contains several hosts.
job variable
BS2000: Job variables are storage areas for the exchange of information between jobs, as well as between the operating system and jobs. They have a name, and also contents (value). The contents can be used for controlling jobs and programs.
The user can create, modify, query and delete job variables. He/she can also instruct the operating system to change the setting of a monitoring job variable if the status of a job or a program is modified.
join file
BS2000: File which contains the user attributes of all the user IDs of a pubset.
kernel
POSIX/UNIX: Code of the POSIX /UNIX operating system.
large file aware
A program is "large file aware" if it processes large POSIX files correctly.
large file safe
A program is "large file safe" if it recognizes large POSIX files and rejects processing in a defined manner, e.g. with an appropriate message.
login directory
See home directory
mount point
POSIX/UNIX: Name of a directory under which a remote resource such as a file tree is mounted.
mounting file systems
POSIX/UNIX: File systems can be mounted in a local file system by means of the command “mount”. The mount point must first be defined as a directory. This directory is no longer visible once the file system has been mounted.
Network File System (NFS)
BS2000: Software product which facilitates distributed data storage in a heterogeneous computer network. Thanks to this facility, the user can access remote files as if they were available on her/his local computer.
operating system
All software and firmware programs which make it possible to operate a computer without requiring tailoring to a specific application. As a rule, the operating system is supplied by the computer manufacturer.
parent process
See fork
password
BS2000: String of characters which the user must enter in order to receive access to a user ID, a file, a job variable, a network node or an application.
path name
POSIX/UNIX: Every file and every directory has a unique path name. The path name specifies the position of the file and directory within the file system and shows how it can be accessed. The path name consists of the names of all superordinate directories, starting from the top of the file system, and the name of the file or directory itself. In each case, the names of the directories are separated from each other by a slash.
(Example: /dir1/dir2/protocol)
A distinction is drawn between absolute and relative path names.
BS2000: Every file cataloged in BS2000 is also clearly identifiable by a path name. The path name consists of the catalog identifier (catid), the user ID (userid) and a fully qualified file name assigned by the user: :catid:$userid.filename
permission bits
POSIX/UNIX: Information on read, write or execute rights for a given file. The bits are divided into three sections: owner, group and other users.
pipe
POSIX/UNIX: Concatenation of two POSIX/UNIX commands. A pipe causes the output of one program to become the input of the next program, with the result that the programs are executed in sequence. A pipe is created when the pipe icon | is specified after the first command. The output of the process to the left of the pipe icon is directed to the process to the right of the pipe icon.
Portable Open System Interface for UNIX (POSIX)
Interface standards for open systems which were defined by the IEEE and are based on UNIX. POSIX contains standards for a wide spectrum of operating system components, beginning with the C programming language, right up to system administration. Among other things, POSIX specifications include:
1003.00 | Guide to POSIX Open System Environment |
| 1003.01 | System Application Program Interface (API) |
| 1003.02 | Shell and Utilities |
| 1003.07 | System Administration |
POSIX administrator
Holder of the POSIX-ADMINISTRATION privilege. This privilege is linked automatically to the SYSROOT system ID and cannot be withdrawn from SYSROOT. The security administrator can also grant this privilege to and withdraw it from other user IDs.
POSIX file system
BS2000/POSIX: File system in BS2000 with the UNIX file structure system (UFS). Like UNIX, it can consist of several file systems. It is structured hierarchically and consists of directories and files (POSIX files). The root directory, which is marked by a slash (/), is located at the top of the hierarchy. The directory structure branches downwards from here. Other files and directories can be branched to from a directory. However, branching from a file is not possible. Every file of a file system can be accessed via precisely one path of the file system.
The difference between a POSIX file system and a UNIX file system is the storage location. In the case of a UNIX file system, the storage location is a physical device, in the case of a POSIX file system, it is a PAM container file.
POSIX shell
BS2000/POSIX: Ported SINIX system program which handles communication between the user and the system. The POSIX shell is a command interpreter. It compiles the input POSIX commands into a language which the system recognizes.
If the POSIX shell is entered for the user attribute “Program”, the POSIX shell is started as soon as the user is connected to POSIX via remote login to POSIX.
public volume set
BS2000: Set of hard disks marked as belonging to the same group. MPVS systems work with several mutually independent pubsets.
pubset
BS2000: Abbreviated form of public volume set
regular file
File which is a freely accessible sequence of bytes without any further structure defined by the system.
relative path name
POSIX: Access path for a file or a directory which starts from the position of the current directory within the file system. Relative path names do not begin with a slash (/).
Reliant UNIX
Successor to SINIX, version 5.43 of which was renamed to Reliant UNIX as a result of the fusion between the former Siemens Nixdorf and Pyramid Technology UNIX versions.
root
POSIX/UNIX: User name (system administrator ID) with the most privileges.
root authorization
ID assigned the user number 0 and the group number 0. The system ID SYSROOT has the root authorization by default.
root directory
POSIX/UNIX: Main directory in a hierarchically structured file system from which all other directories branch.
security attributes
BS2000: Attributes of an object relevant to security (file, job variable etc.) which determine the type and possibility of data access to this object.
The following security attributes exist for files, for example: ACCESS/USER-ACCESS, SERVICE bit, AUDIT attribute, RDPASS, WRPASS, EXPASS, RETPD, BACL and GUARD.
shareable file
BS2000: A file which the user cataloged with the operand USER-ACCESS=*ALL-USERS. Files which are marked as shareable in this way can be invoked by all users. However, the user is required to know the user ID of the generator of the file and, if necessary, to specify the password if the file is password-protected.
shutdown
BS2000: Procedure for an orderly system termination sequence, including the saving of specific system files.
Sockets
Interface for network access via TCP/IP
special file
File, also referred to as a device driver, that is used as an interface to an I/O device (e.g. terminal, disk drive).
startup
BS2000: Loading the BS2000 operating system software. There are three variants:
AUTOMATIC-STARTUP
DIALOG-STARTUP
FAST-STARTUP
These variants differ in degrees of automation.
subdirectory
POSIX/UNIX: Directory subordinate to a directory on the next highest level of the file system.
system privileges
BS2000: All privileges which can be assigned by means of the /SET-PRIVILEGE command, as well as the privilege of the security administrator and the TSOS system ID.
UNIX File System (UFS)
File system variant of the Virtual File System for the administration of local file systems.
UNIX operating system
An interactive operating system, developed in 1969 by Bell Laboratories. Since only a central kernel of UNIX is hardware-dependent, UNIX is used on many different systems from different manufacturers.
user
BS2000: Represented by a user ID. The term “user” is a synonym for persons, applications and procedures etc. which can obtain access to the operating system via a user ID.
user administration
BS2000: Involves administration of user IDs and user groups in relation to resources and user rights, as well as the creation, modification and deletion of user IDs and user groups.
user attributes
BS2000/POSIX: All the features of a user ID which are stored in the user ID catalog.
user catalog
See join file
user group
BS2000: Collection of individual users under one name.
user ID
POSIX/UNIX: Positive integer which serves to identify a system user.
user privileges
BS2000: All attributes assigned to a user ID and stored in the join file which displays privileges.