Section three: Requirements for systems

11 Requirement for the description of systems

This International Standard specifies that certain information shall be communicated between a user and an implementation (see clauses 12 and 13).

An information processing system that conforms to this International Standard shall be the subject of a description which identifies the means by which the user may supply such information, or may obtain it when it is made available, as specified in this International Standard.

12 Requirements for an originating system

12.1 General

The implementation shall be capable of recording a set of files, and all descriptors that are specified in this International Standard, on a Volume Set in accordance with one of the interchange levels specified in this International Standard.

12.2 Files

The implementation shall obtain from the data preparer the information that constitutes the set of files to be recorded.

12.3 Descriptors

12.3.1 The implementation shall allow the data preparer to supply the information that is to be recorded in each of the descriptor fields listed below, and shall supply the information for a field if the data preparer does not supply it.

For the Primary Volume Descriptor:

For each Path Table Record:

For each Directory Record:

12.3.2 The implementation shall allow the data preparer to supply the information that is to be recorded in the descriptor fields listed below, and shall not record the Supplementary Volume Descriptor or the Enhanced Volume Descriptor if the data preparer does not supply the information.

For each Supplementary Volume Descriptor or Enhanced Volume Descriptor:

12.3.3 The implementation shall allow the data preparer to supply the information that is to be recorded in the descriptor fields listed below, and shall not record the Volume Partition Descriptor if the data preparer does not supply the information.

For each Volume Partition Descriptor:

12.3.4 The implementation shall allow the data preparer to supply the information that is to be recorded in the descriptor fields listed below, and shall not record the Boot Record if the data preparer does not supply the information.

For each Boot Record:

12.3.5 The implementation shall allow the data preparer to supply the information that is to be recorded in the descriptor fields listed below, and need not record the Extended Attribute Record if the data preparer does not supply the information for any of the descriptor fields listed below. If the Extended Attribute Record is recorded, the implementation shall supply the information for a field if the data preparer dose not supply it.

For each Extended Attribute Record:

12.4 System Area

The implementation shall allow the data preparer to supply the information that is to be recorded on the Logical Sectors with Logical Sector Numbers 0 to 15.

13 Requirements for a receiving system

13.1 General

The implementation shall be capable of reading the files and the recorded descriptors from a Volume Set that has been recorded in accordance with one of the interchange levels specified in this International Standard, except Associated Files.

13.2 Files

The implementation shall make available to the user the information that constitutes the recorded files, except any Associated File.

If the implementation allows the user to specify that the information constituting a file is to be interpreted according to 6.10, the implementation shall make available to the user the length of each record in the file.

13.3 Descriptors

13.3.1 The implementation shall allow the user to supply information sufficient to enable the implementation to locate the files required by the user, and to locate the volumes on which these are recorded.

13.3.2 The implementation shall make available to the user the information that is recorded in each of the descriptor fields listed below.

For the Primary Volume Descriptor:

For each Supplementary Volume Descriptor or Enhanced Volume Descriptor:

For each Path Table Record:

For each Directory Record:

13.4 Restrictions

The implementation may impose a limit on the length of a record to be made available to be user. The implementation is not required to make available to the user any byte beyond the first n bytes of a record, where n is the value of the imposed limit.

13.5 Levels of Implementation

This International Standard specifies two nested levels of implementation.

13.5.1 Level 1

At Level 1 the implementation is permitted not to make available to the user:

13.5.2 Level 2

At Level 2 no such restrictions shall apply.