One Convergence Interview Experience

Interview Questions :
As my area of Interest was Unix Network Programming so he started asking from that.

1. Difference between file descriptor and file Pointer?
2. Suppose a process reads/writes something from a file and the same content should be printed on the console.How you will do?
3. How does printf and scanf work in the background ?
4. Suppose a parent process open a file for reading and later forks a child process.Then from where would the child process begin reading in the file(either from start or after some bytes)? Explain what will be the difference when file is opened once using open and later using fopen ?

Then he saw my resume again, and started asking from C and OS(as it was mentioned there).

1. He gave me a structure and asked me the sizeof() of that structure.
2. Then he asked me the complete concept of Structure Padding in detail(within memory).
3. He asked me the concepts of Internal and External Fragmentation.
4. What is Paging , and Segmentation related concepts.
5. Bit manipulation related Questions :
1. Suppose you have a decimal number then write the logic to find the number of 1's in its binary.
2. Asked about all the bitwise operators and their uses.
6. Asked about strings and to implement strcmp.

 These all questions were asked in first round(around 45 minutes).

Source: Aditya Singh(M.Tech(CS))