Computer Science 330
Operating Systems

Fall 2025, Siena University

Home     Syllabus     Schedule

Agenda

• Announcements
  • CS holiday party - reading day at 1:30 - be there!
  • The next readings/activities from OS zyBook
    • Chapter 19, Sections 4-5, Chapter 22, due Monday, December 1
    • Chapter 22, due Friday, December 5
  • Programming Project 5: Roger Bacon Shell with Pipes and Redirection [HTML] [PDF] remaining functionality due December 3
• File Systems
  • File system interface
    • file concept
    • file system - organized collection of files
    • file attributes
    • file operations
    • file types
  • Directories - listings of files
    • directory concept
    • directory operations
    • directory organization
      • single-level
      • two-level
      • tree-structured
      • acyclic-graph: links/shortcuts/aliases
      • general graph: upward-pointing links create cycles
    • directory implementation
      • linear list
      • hash tables
  • Disks and partitions
    • a system may have multiple disks, each of which contains multiple partitions
    • we create a file system (more later) in each partition
    • mounting: drive letters in Windows, paths in Unix
    • In Unix, a virtual file system layer translates generic paths to the correct partitions (local of varying types, network-accessible)
    • partitioning: why and how?
  • File System Implementations
    • want to provide: convenience, protection, efficiency
    • issues:
      • allocation of disk blocks to files/directories
      • track available blocks
      • do this efficiently
• Looking at a couple of the exercises for OS zyBook Chapter 19
  • 19.2.1, 19.2.2
• Lab and project work

Examples

• https://github.com/SienaCSISOperatingSystems/morelinks-example