BS 6542-2:1988

National foreword
Committees responsible
Section one. General
0 Introduction
1 Scope and field of application
2 Conformance
3 References
4 Definitions
5 Notations
Section two. Requirements for the medium
6 Volume structure
7 Contents of a file
8 Recording of descriptor fields
9 FDC Descriptor
10 File Allocation Table
11 File directories
Section three. Requirements for systems
12 Requirements for the description of systems
13 Requirements for an originating system
14 Requirements for receiving system
Section four.
15 Record structure
Annexes
A Parameter values for FDCs conforming to an
    International Standard for data interchange
B Parameter values for other FDC formats
C ISO 646: International Reference Version (IRV)
D Example of volume structures and file location
E Index of acronyms

Gives flexible disk cartridges volume and file structure for interchange of information between users with optional record structure. Suitable for flexible disk cartridges and other types. Shows location of files of information on a flexible disk cartridge, and defines a set of recorded descriptors identifying files which may be interchanged, their locations and attributes, the location of defective and unused space for recording, the attributes of the FDC and of the descriptors recorded on it. Describes requirements for system interchange and functions within systems which originate or receive FDC's. Provides method for space allocation independent of the file numbers recorded. Allows files sizes to be changed during processing.

This International Standard specifies the volume and file structure of flexible disk cartridges (FDC) for the interchange of information between users of information processing systems. It also specifies an optional record structure.

This International Standard is applicable to various types of flexible disk cartridges including those identified in clause 3, and other types which may be the subject of future International Standards.

This International Standard specifies the location of files of information on a flexible disk cartridge, and also specifies a set of recorded descriptors which identifies:

• the files which may be interchanged;
• the locations of the files;
• the attributes of the files;
• the location of unused space for recording on the FDC;
• the location of defective recording space on the FDC;
• the attributes of the FDC and of the descriptors recorded on it.

This International Standard also specifies requirements for the processes which are provided within information processing systems to enable information to be interchanged between different systems, utilizing recorded flexible disk cartridges as the medium of interchange. For this purpose it specifies the functions within systems which are intended to originate or to receive flexible disk cartridges which conform to this International Standard.

This International Standard provides a method for the allocation of space that is independent of the number of files that are recorded on the volume. It also enables the sizes of the recorded files to be expanded or contracted during processing, subject only to the availability of unused recording space when needed.

The contents and organization of the files are not specified by this International Standard and are subject to agreement between the originator and the recipient of the interchanged FDC.