file system

Work in Progress

Concept

File

  • locgial unit of information created by process
  • abstact data type, with a set of operations with several implementations
  • contains:
    • data - structured in some way, program must know how to read it
    • metadata/attributes - information associated with the file
  • types:
    • regular files
    • directories
    • special files

File metadata

  • name - human readable reference
  • identifier - unique id used by the file system
  • type - indicates the use of the file
  • size - size in bytes
  • protection - access permissions
  • time - creation/modification time
  • owner - owner user id
  • table of content - information for the file system to determin how to access the file

File protection

  • controlled access to the information stored in a file
Type of accessDescription
readsee the contents of the file
writewrite to/rewrite the file
executeload into memory and execute
appendadd new information to the end of the file
deleteremove file from file system
listread metadata