公开(公告)号：CA1281424C

公开(公告)日：1991-03-12

申请号：CA557767

申请日：1988-01-29

Applicant: IBM

Inventor： FLANNAGAN WILLIAM J ,  KERN RONALD M ,  KULAKOWSKI JOHN E ,  WAGNER ROBERT E

IPC: G06F12/00 ,  G06F3/06 ,  G06F17/30 ,  G11B7/007 ,  G11B20/12 ,  G11B20/18 ,  G11B27/28 ,  G11B27/32 ,  G11B7/013

Abstract: An updatable and expandable directory structure and resultant access procedures emulating a write-once or indelible record medium to a rewriteable record medium as to accessing characteristics. The directory is indexed; one directory header for a first set of files indexes another set of files. Sector clusters or data extents are managed such that random recording from any file proceeds independently of write-once characteristics. The directory is stored on the medium as data is recorded. Each directory entry contains an archival history of recording of a related data file in the medium. Both logical and physical addressing is employable. TU985007