Operating Systems


  • Course: Operating Systems (CO20-320202)
  • Semester: Fall 2019
  • Instructor: Jürgen Schönwälder
  • TA: Shala, Ardit
  • TA: Mana, Irsida
  • Class: Monday, 08:15-09:30 (R.1-53 Lecture Hall)
  • Class: Thursday, 09:45-11:00 (R.4-52 Conference Room)
  • Class: Friday, 13:00-14:00 (R.1-53 Lecture Hall)
  • Final Exam: Monday, 2019-12-09 09:00-11:00 (SCC Hall 3)
  • Makeup Exam: Friday, 2020-01-31 17:00-19:00 (East Hall 4)
  • Office: Monday, 11:15-12:30 (Research I, Room 87)


This course provides an introduction to the concepts underlying operating systems. Students will develop an understanding how operating systems realize a virtual machine that can be used to execute multiple concurrent application programs. The course discusses resource allocation algorithms and how concurrency problems can be solved.

Topics: Operating system architectures, system calls and interrupts, concurrent processes and threads, scheduling, synchronization, deadlocks, virtual memory, file systems, inter-process communication, socket programming interface.


  • Abraham Silberschatz, Peter B. Galvin, Greg Gagne: "Applied Operating System Concepts", John Wiley, 2000
  • Andrew S. Tanenbaum, Herbert Bos: "Modern Operating Systems", Prentice Hall, 4th edition, Pearson, 2015
  • William Stallings: "Operating Systems: Internals and Design Principles", 8th edition, Pearson, 2014
  • Robert Love: "Linux Kernel Development", 3rd edition, Addison Wesley, 2010
  • Robert Love: "Linux System Programming: Talking Directly to the Kernel and C Library", 2nd edition, O'Reilly, 2013
  • Allen B. Downey: "The Little Book of Semaphores", Version 2.2.1, Green Tea Press, 2016


Monday Thursday Friday Topics
2019-09-02 2019-09-05 Introduction, Libraries, Function Call, System Calls, Tools
2019-09-09 2019-09-12 Hardware, Processes, Threads
2019-09-16 2019-09-19 Synchronization (Mutual Exclusion, Semaphores)
2019-09-23 2019-09-26 Synchronization (Condition Variables, Monitors, Deadlocks)
2019-09-30 2019-10-03 Deadlocks, CPU Scheduling
2019-10-07 2019-10-10 Memory Segments, Memory Mapping, Linking
2019-10-14 2019-10-17 Memory Management (Segmentation, Paging, Working Sets)
2019-10-21 2019-10-24 Inter-Process Communication (Signals, Pipes)
2019-10-28 2019-10-31 Inter-Process Communication (Sockets)
2019-11-04 2019-11-07 Inter-Process Communication (Event Loops)
2019-11-11 2019-11-14 2019-11-15 File Systems
2019-11-18 2019-11-21 2019-11-22 Block and Character Devices
2019-11-25 2019-11-28 Virtualization, Virtual Machines, Container
2019-12-02 2019-12-05 Distributed Systems


Date/Due Name Topics
2019-09-16 Quiz #1 system calls vs library calls, dynamically vs. statically linked executables
2019-09-23 Sheet #1 library vs. system calls (scat), repeated execution (watch)
2019-09-30 Quiz #2 process and threads, race conditions, critical sections, semaphores
2019-10-07 Sheet #2 multi-threaded coin flipping (pthreads and mutexes)
2019-10-14 Quiz #3 semaphores, semaphore pattern, mutexes and condition variables
2019-10-21 Sheet #3 detectives meeting clients (posix mutexes and condition variables)
2019-10-28 Quiz #4 linking, memory management (segmentation, paging)
2019-11-04 Sheet #4 page replacement algorithms, dynamic loaded object files
2019-11-11 Quiz #5 virtual memory, signals, pipes
2019-11-18 Sheet #5 word guessing game server (sockets)
2019-11-25 Quiz #6 file systems
2019-12-02 Sheet #6 file systems and overlay file systems


The final grade is made up of homeworks/assignments (30%), bi-weekly quizzes (30%), and the final exam (40%).

Electronic submission is the preferred way to hand in homework solutions. Please submit documents (plain ASCII/UTF-8 text or PDF, no Word) and your source code (packed into a tar or zip archive after removing all binaries and temporary files) via the online submission system. If you have problems, please contact one of the TAs.

Late submissions will not be accepted. Homeworks may need to be defended in an oral interview. In case you are ill, you have to follow the procedures defined in the university policies to obtain an official excuse. If you obtain an excuse, the new deadline will be calculated as follows:

  1. Determine the number of days you were excused until the deadline day, not counting excused weekend days.
  2. Determine the day of the end of your excuse and add the number of day you obtained in first step. This gives you the initial new deadline.
  3. If the period between the end of your excuse and the new deadline calculated in the second step includes weekend days, add them as well to the new deadline. (Iterate this step if necessary.)

For any questions stated on assignment sheets, quiz sheets, exam sheets or during makeups, we by default expect a reasoning for the answer given, unless explicitely stated otherwise.

Students must submit solutions individually. If you copy material verbatim from the Internet (or other sources), you have to provide a proper reference. If we find your solution text on the Internet without a proper reference, you risk to lose your points. Any cheating cases will be reported to the registrar. In addition, you will lose the points (of course).

Any programs, which have to be written, will be evaluated based on the following criteria:

  • correctness including proper handling of error conditions
  • proper use of programming language constructs
  • clarity of the program organization and design
  • readability of the source code and any output produced

Source code must be accompanied by a README file providing an overview of the source files and giving instructions how to build the programs. A suitable Makefile is required if the build process involves more than a single source file.

If you are unhappy with the grading, please report immediately (within one week) to the TAs. If you can't resolve things, contact the instructor. Problem reports which come late, that is after the one week period, are not considered anymore.

The policy on makeup quizzes is the following: There won't be any quiz makeups. If you (a) get an official excuse for a quiz from the registrar's office or (b) approach we well in advance of the quiz with a very good reason for not being able to participate (e.g., because you take a GRE computer science subject test at the day of a quiz), then the weight of the final exam will be increased according to the weight of the quiz you got excused for.