Before Recitation

This paper requires an MIT personal certificate for access: The UNIX Time-Sharing System. This recitation will focus on the last half of the paper (starting with section 5). (If you're having trouble accessing the paper, here is a nearly-identical version that doesn't require certificates.)

After reading section 5, you should understand the basics of processes in UNIX (e.g., how fork() works, how memory is shared, how processes communicate). After reading section 6, you should understand the basics of the shell. For instance, you should be able to describe what happens if you type sh into the UNIX shell (how many processes would be running?). Sections 7-10 wrap up the authors' discussions on UNIX.

As you read, think about the following:

  • What 6.1800 concepts are exemplified by UNIX?
  • What design principles, or objectives, do you think the authors were following as they developed UNIX?

Question for Recitation: Before you come to this recitation, you'll turn in a brief answer to the following questions (really—we don't need more than a sentence or so for each question). Your TA will be in touch about exactly how to turn that in. Your answers to these questions should be in your own words, not direct quotations from the paper.

  • What does the UNIX shell do?
  • How does it work?
  • Why is it useful?
  • How do you think the UNIX developers envisioned their system being used in 2023, if at all?
As always, there are multiple correct answers for each of these questions.

During Recitation

We expect you to be engaged and participate in recitation, and there are many ways to do that! Check out our participation FAQ for more information.

After Recitation

Outline for this recitation.