The catalog input/output system [by] Martin Kay, Frederick Valadez, and Theodore Ziehe.
A complete definition of the format used for catalogs on magnetic tape and a description of the routines of the Catalog Input/Output System. Catalog maps, catalog data, and tape labels are written as logical records in a specially designed blocking format. Beginnings and ends of blocks, physical tapes, and catalogs are explicitly marked. The Catalog Input/ Output System offers a variety of input/ output unit-control operations in addition to the commands for reading and writing data in catalog format. The reading and writing commands for reading and writing and writing data in catalog format. The reading and writing commands are implemented on three levels: Level III handles individual data; Level II reads and writes logical records; and Level I processes blocks of information.