Citrix Systems Senior Software Engineer Interview

Interview Details – Initially, got a call from HR and got the phone interview. Then had the onsite with 5 people.

Questions asked on phone-screen?
- Difference between mutex and semaphore? When to use which one?
- Why synchronization is needed?
- Difference between thread and a process?
- What happens at context switch?
- What's a PCB? What's a stack, code, heap and data section? What kind of variables go in each section?
- What's a logical address? How does the translation happens between logical and physical address?
- What happens when an application calls a system call?
- Difference between TCP and UDP?
- What are socket calls?
- What's a three-way handshake?
- How is a TCP connection established? How does the connection teardown happen?
- What's an extern variable in C?
- How can you tell the endian-ness? Little vs Big programmatically

Onsite was scheduled with 5 people and everyone asked programming questions like...
- Write a C program to merge two link lists together?
- Write a macro to choose highest of three numbers?
- Write a C program to see if bits in a char are a palindrome?
- Write a C program to reverse a singly link-list? Can you reverse without modifying pointers?
- Take an example of a CD player, how do the sort and rand works in this case. E.g. randomly sort the songs?
- You have a list of 1000's of long urls. How would you store these?
- In an active and standby model, say you have 5 IPs on Active and active dies. When standby comes up, how do you deal with unique IP addresses redundancy?
- In a char or int, you just have one bit set. Write a program to find out which bit is set?

Reason for Declining – Half of the development team was in India. I didn't want to deal with the offshore meetings at odd times.