I was invited onsite after an initial phone screen by the hiring manager. I did not have much experience in file system development, and my resume showed it. In fact, I had developed a stacked file system, and that was my only experience.

The interview consisted of four engineers taking turns asking me coding and technical questions.

• The first interviewer asked me some questions about file system implementation, and I answered from my experience.
• The second interviewer was, in my opinion, the least knowledgeable among them all. He asked me how malloc works. When I said it calls the kernel for allocating more heap memory when it's short, he was shocked and started arguing that I was wrong.
• The third interviewer bombarded me with 15 coding questions (reverse linked list, reverse string, etc.), which were a cakewalk for me.
• The fourth interviewer asked me a question about sorting integers. When I started the answer with an insertion sort for a linked list, the problem statement changed from an insertion problem to a const array sort problem, and he wanted me to say heap sort was the best answer. However, he didn't hesitate to tell me that he wanted a discussion, not a memorized answer. Funny!

The hiring manager was decent enough to call me and tell me that the team thought I didn't have enough file system experience. He said he would recommend me for other positions. Didn't my resume already say that? So why waste my time?

Reverse string.

Implement malloc.