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File Descriptors, Open-File Tables, and Reference Counting

This generated surface maps a learner-facing curriculum unit to its canonical source routes.

Curriculum surface​

  • Open learner-facing unit
  • Curriculum path: content/curriculum/systems/semester-05-os-networking/module-04-file-systems-io/concepts/cluster-01-the-file-abstraction/03-file-descriptors-open-file-tables-and-reference-counting-primary.md
  • App: systems
  • Semester: semester-05-os-networking
  • Module: module-04-file-systems-io
  • Unit kind: concept
  • Curation level: module_curated

Learning objectives​

  • Explain File Descriptors, Open-File Tables, and Reference Counting as part of the full syscall-to-storage path rather than as an isolated filesystem fact.
  • Reason about correctness, crash behavior, and performance tradeoffs that appear when File Descriptors, Open-File Tables, and Reference Counting is used in real programs.
  • Use ostep to connect the learner page to concrete APIs, on-disk structures, and I/O debugging evidence.

Prerequisites​

  • Comfort with processes, memory, and the syscall boundary from the earlier OS modules.

Source books​

  • ostep

Source routes​

Ostep​

Supporting curriculum routes​

No supporting curriculum routes linked yet.

External enrichment​

  • man 2 open (official_docs_companion) - Grounds file-descriptor and file-opening concepts in the system call interface itself.
  • man 2 read (official_docs_companion) - Useful when learners need to connect filesystem ideas to concrete blocking, partial-read, and error behavior.

AI companion modes​

  • Explain simply
  • Socratic tutor
  • Quiz me
  • Diagnose my confusion
  • Generate extra practice

Source-of-truth note​

This teaching unit is learner-facing guidance. Its canonical source backbone is the referenced book ostep, and outside material should only clarify or strengthen that backbone.