ch08 - Chapter 8 File Management Understanding Operating...

Info iconThis preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon
Chapter 8 File Management Understanding Operating Systems, Fourth Edition
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Understanding Operating Systems, Fourth Edition 2 Objectives Objectives You will be able to describe: The fundamentals of file management and the structure of the file management system File-naming conventions, including the role of extensions The difference between fixed-length and variable- length record format The advantages and disadvantages of contiguous, noncontiguous, and indexed file storage techniques Comparisons of sequential and direct file access
Background image of page 2
Understanding Operating Systems, Fourth Edition 3 Objectives (continued) Objectives (continued) You will be able to describe: The security ramifications of access control techniques and how they compare The role of data compression in file storage
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Understanding Operating Systems, Fourth Edition 4 File Management File Management File Manager controls every file in system Efficiency of File Manager depends on: How system’s files are organized (sequential, direct, or indexed sequential) How they’re stored (contiguously, noncontiguously, or indexed) How each file’s records are structured (fixed-length or variable-length) How access to these files is controlled
Background image of page 4
Understanding Operating Systems, Fourth Edition 5 The File Manager The File Manager File Manager is the software responsible for creating, deleting, modifying, and controlling access to files Manages the resources used by files Responsibilities of File Managers: Keep track of where each file is stored Use a policy to determine where and how files will be stored Efficiently use available storage space Provide efficient access to files
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Understanding Operating Systems, Fourth Edition 6 The File Manager The File Manager (continued) (continued) Responsibilities of File Managers: (continued) Allocate each file when a user has been cleared for access to it, then record its use Deallocate file when it is returned to storage and communicate its availability to others waiting for it
Background image of page 6
Understanding Operating Systems, Fourth Edition 7 The File Manager The File Manager (continued) (continued) Definitions: Field: Group of related bytes that can be identified by user with name, type, and size Record: Group of related fields File: Group of related records that contains information used by specific application programs to generate reports Sometimes called flat file; has no connections to other files Database: Groups of related files that are interconnected at various levels to give users flexibility of access to the data stored
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Understanding Operating Systems, Fourth Edition 8 The File Manager The File Manager (continued) (continued) Program files: Contain instructions Data files: Contain data Directories: Listings of filenames and their attributes Every program and data file accessed by computer system, and every piece of computer software, is treated as a file File Manager treats all files exactly the same way as far as storage is concerned
Background image of page 8
Image of page 9
This is the end of the preview. Sign up to access the rest of the document.

Page1 / 56

ch08 - Chapter 8 File Management Understanding Operating...

This preview shows document pages 1 - 9. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online