CS 3733 Operating Systems, Spring 2003 Midterm Exam Comments
We will go over the exam in class.
The class average was 76 and the grade distribution was as follows:
- 90's: 10
- 80's: 17
- 70's: 11
- 60's: 10
- 50's: 3
- 40's: 3
Comments about individual problems:
- The question did not ask what a buffer was.
While the term buffering may have several meanings, it has only
one definition as discussed in the class
notes,
and the term spooling
should not be ambiguous.
- This was similar to a problem at the beginning of the notes on
Fork
- Most people figured out that in the first case the processes read different
parts of the file and in the second case they both read from the beginning
of the file. Some people knew that the output could be interleaved.
Few realized that requesting 5 bytes does not mean that 5 bytes would be
read.
- This problem related to the diagram in Figure 4.1 of the Silberschatz
text and discussed in class. Note that when a child terminates this
could cause the parent to return from a wait.
- Part b) gave people the most trouble. If not process is able to write
to a pipe, then a read will return 0, indicating end of file.
- This was similar to the problem given in class on
January 28.
- Few people had trouble with this one.