Qualcomm Software Engineer Linux Kernel interview questions

I had a technical telephonic interview which lasted for about 45 minutes. I had applied online on their website and got a call in 2 weeks time to schedule for a telephonic interview. I prepared a lot of basic C interview questions and fundamentals of OS. I should have done more preparation regarding some of the projects that I worked on as I was not very confident in the way I explained to him some of the OS fundamentals that was used in some of my relevant projects.

Technical phone screen. Was asked typical questions relating to my resume, why Qualcomm? If you are currently already doing a similar job why change? Was asked typical OS questions, like: What happens during a context switch? What is a PCB? What are some of the things in the Linux task_struct. Q) Write algorithm to find missing element in array. For example int array[5] = {1, 2, 0, 3, 4}; this array should contain # from 1 to 5. # 5 is missing. Q) How would you write a mem alloc routine that is 32 byte aligned. Q) How would you figure out if the stack grows up or down. A) char *ptr; printf(" 0x%lx \n",ptr); ptr++; printf(" 0x%lx \n", ptr); The guy was a little hard to understand at times.