Cataloged data sets

The operating system has facilities that automatically record the following information about each of your data sets:
  • The data set name
  • The serial numbers of the volume or volumes containing the data set
  • The type of device on which the volumes should be mounted
  • The data set's relative position on its first volume

The information is indexed by the data set name and recorded on a direct access device in a logical structure called the catalog. You can retrieve a cataloged data set by specifying its name in the DD statement and omitting the volume serial. The system finds the associated information in the catalog and issues a command, to either the operator or the tape library, to mount the cartridge on a drive.

Parent topic: Tape information recorded elsewhere