I. C Programming
1. What is the * operator? What does it do?
2. What is the & operator? What does it do?
3. What’s the difference between char c[80] and char *c?
…what about when they’re used in sizeof()?
4. What do common C functions do? How are they called?
String Functions: strcpy(), strlen(), strcmp()
Memory Functions: malloc(), remalloc(), free()
I/O Functions: printf(), fgets(), fgetc(), read(), write(), fread(), fwrite()
Thread-related Functions: pthread_create(), pthread_join(), pthread_detacth()
Semaphore-related Functions: sem_init(), sem_destroy(), sem_post(), sem_wait()
… and others.
5. What is NULL?
6. Understand how to trace and write pointer code.
7. What’s the difference between a stack and a heap variable? What about global and static
variables?
II. Operating Systems
1. What is the difference between a function call and a system call?
2. - What is an example of a purely function call? Any string function.
- What is an example of function call that is a thinly wrapped system call? Fork(), fread(), fopen()
- Why does printf() not fit in either category? It only makes a system call when necessary. (i.e.
when it writes to the screen)
3. What is the difference between a process and a thread?
4. How do a user-thread and a kernel-thread differ?
5. What are the different states that a process may be in within in operating system?
6. What is a zombie thread? What is an orphan thread?
7. What are the return values of fork()?
8. What parts of memory are retained when fork() is called?
9. How do you abandon a thread? How do you kill it? How do you wait for it to finish?
10. What does it mean for a function to be thread-safe?
III. Synchronization
1. When is synchronization needed?
2. What is the difference between a semaphore and a mutex? Can you use mutexes in place of a
semaphore?
3. What is a critical section?
4. What is deadlock? What other properties are there in relation to synchronization?
5. How does semaphores and testandset() differ?
6. What are algorithms learned in class to deal with synchronization?
7. How do you define a POSIX semaphore in C? What are the two main function calls to use it? How
to you clean up the memory associated with a semaphore?
IV. Scheduling
1. Why do processes need to be scheduled?
2. How do you schedule with a FIFO policy? SJF? Round robin?
3. What does it mean for a scheduling algorithm to be preemptive?
4. How does bounded wait apply to scheduling? What is starvation? What is the convey effect?
