SDE - 2

What's an OS, Various OS services. What OS manages and how?

Then he asked if two or more processes want to access the same resource. What can happen?

What is a race condition?

What is a TSL? How locks can be implemented in OS?

What is a Semaphore? How it can be implemented? He made me to write the codes for implementation.

Difference between mutex and semaphore?

You have been given an integer 'N'.

Your task is to return true if it is a power of two. Otherwise, return false.

An integer 'N' is a power of two, if it can be expressed as 2 ^ 'K' where 'K' is an integer.

For example:

'N' = 4,
4 can be represented as 2^2. So, 4 is the power of two, and hence true is our answer.

Torch and Bridge

There are 4 persons (A, B, C and D) who want to cross a bridge in night. A takes 1 minute to cross the bridge. B takes 2 minutes to cross the bridge. C takes 5 minutes to cross the bridge. D takes 8 minutes to cross the bridge. There is only one torch with them and the bridge cannot be crossed without the torch. There cannot be more than two persons on the bridge at any time, and when two people cross the bridge together, they must move at the slower person’s pace. Can they all cross the bridge in 15 minutes?

1. What is Code Motion?
2. What are the different phases of compilation process?
3. Explain Lexical Analysis?
4. What are macros? What are inline functions?
5. What is recursion? Write a recursive code for zigzag traversal of tree?
6. Explain how recursion works? How recursion goes back to the calling statement after the
based condition is executed?
7. What is Program Counter? What is PCB?
8. Why is relocation needed?

1. What is an interrupt?
2. How are interrupts handled? Explain with an example.
3. How ISR works? What happens when an interrupt is raised?
4. Is there any table involved in the whole process?

It was very easy as expected. We had a chit chat about Qualcomm flagship SoCs.
Regular questions about technology to work upon, location preference and so on.