Computer Science 432 Operating Systems Williams College Fall 2006

Agenda

• Announcements
  • Steve Freund is giving the Sigma Xi talks this semester. Thursday and Friday, 4:15.
• Exam back - brief recap
• Unix Systems Programming (see details on last week's lecture notes)
  • Pipes
  • Duplicating File Descriptors
• Deadlock
  • Idea
  • Necessary conditions: mutex, hold and wait, no preemption, circular wait
  • Resource allocation graphs
  • Prevention

Lecture Assignment

Due at the start of class, Thursday, October 26.

Turn in short answers to these questions. Please turn in a hard copy (typeset or handwritten are OK). We will discuss these questions during class, so no late submissions are accepted.

• SG&G 7.1
• A system has two processes and three identical resources. Each process needs a maximum of two resources. Is deadlock possible? Why or why not?

The readings for next time are SG&G Chapter 8.

Examples

• One-lane tunnel
  (Along the Needles Highway)
  
• Williamstown water main repair
  (Not too long ago...)
  
• Banker's Algorithm Examples