CS 356 - Operating Systems - Spring 2010


Blue Screen of Death
When operating systems fail. To be avoided.

We use operating systems every day, and we interact with them constantly, but primarily on a superficial level. The operating system exists, from the user's perspective, to let us run applications and manage data. As usual, there is a great deal of complexity hidden underneath that usage.

Operating Systems sit between applications and the hardware. They manage resources, such as memory, processor time, and storage space, to present clean, usable interfaces on which applications can be built.

This course will explore some of the fundamental concepts of operating systems, giving you an understanding of how they work that will inform your development of programs that run on top of them.

For an idea of the specific topics covered in the course, see the rough schedule for the semester.


When/Where: MWF 10:00-10:50PM / CNS E201

Instructor: Mark Liffiton
Office: CNS C207B
Office Hours: Mon 2-5; Tue/Thu 10:40-12:00; (by appointment only: Wed/Fri 2-5)
Contact: Email is preferred (please start the subject with "CS356:"). For more pressing matters, my office # is 309-556-3535.

Textbook: Modern Operating Systems (third edition) by Andrew S. Tanenbaum
ISBN: 9780136006633

Other Pages

Semester schedule — tentative - see the Moodle for up-to-date details.

Moodle — assignments, quizzes, announcements, and other online resources will be posted here.


The final grade will be based roughly on the following breakdown:

Exam 115%
Exam 215%
Final Exam20%


* You can create PDFs from any document in OS X (instructions) or in Windows (using a free tool like DoPDF).

Assignments will be posted on the course's Moodle site, usually about a week before they are due, and they will be collected there as well. Submissions should be in the form of plain text or PDF*. I will aim to get them graded and returned to you by the following week.

Your lowest assignment score will be dropped.


As a Writing Intensive course, several papers will be assigned throughout the semester. We will focus on certain types of written material and particular mechanics of writing with the overall goal of improving writing skills. Revision is a crucial component of improving one's writing, and it will feature prominently in the course. Papers should be submitted as PDFs on the Moodle.


There will be two exams during the semester, held in class. The final will be held during the final period, time TBD.


As you may have heard from other teachers: If everyone does well, that's great! I'm not going to lower anyone's grade to fit some predetermined grade distribution. However, scores given on individual quizzes and exams (especially exams) may not translate directly into a letter grade on the traditional scale. As explained quite well here:

"A percentage shows how much of a particular exam was dealt with successfully, but what test is so perfect that it could completely determine extent of knowledge or ability? If a student gets a grade of 90%, it does not mean they know 90% of everything in the subject. Wise students will begin to look at scores as a place on a continuum of achievement rather than analysis carved in stone."

Late Policy

Assignments and papers will be due at set times; they will be considered late at any point after that time. An assignment or paper will lose 10% of the total possible points for every day it is late, and after five days it will not be accepted.

Assignments can't be accepted at all after solutions have been handed out or the graded work has been returned to the class.


If you would like to request a regrade, submit a request in writing (via email) within one week of receiving the graded assignment, exam, etc. Indicate exactly which part you believe deserves a different score and why.

Engagement / Attendance

Class time will be complementary to the reading, and you will need both in order to learn all of the material in this class. Furthermore, each student benefits from the engagement of all others in the class. Ten points of your final grade will be based on that engagement. Attending every class period on time and prepared will earn a base of 7 points; points can be gained by constructive participation, in class or out, such as asking questions, answering them, responding in the forum, sharing insights or useful/interesting resources with the class (posting in the forum, for example), investigating concepts beyond the requirement in class, working on small independent learning projects, and in many other ways; points can be lost for excessive (more than 3) unexcused absences, disrupting class (e.g., regularly showing up late), dominating the conversation, and the like.

Absences can be excused with documentation from health services or the Dean of Students' office, or if arrangements are made with me more than a week in advance. In general, if you know you will be missing a class, let me know as soon as you do.

Working with Others

I strongly encourage you to form study groups with your classmates, compare notes, explain concepts to one another, and generally help each other learn the material in this course.

Any material turned in for a grade must be your own individual work, though. You may work on concepts with other students, but I ask that you not discuss assigned problems until after the work has been turned in. This has two goals: 1) let the grades be a reflection of each student's own work, and 2) avoid situations where one person solves a problem and another records the answer as their own work without really learning. I understand that the line between discussing concepts and solving problems can be vague, so I ask that you use your own judgement with those two goals in mind and ask me if a situation is unclear.

Try to follow this rule of thumb: No matter what help you received figuring out the concepts involved, when you turn something in you should be able to reproduce the whole thing, working through the assignment again, without any outside help.

For details on the university's policies regarding academic honesty, please read the sections of the student handbook on conduct, cheating, and plagiarism here.