Firstly there is phone interview from the hiring manager, which involves lots of technology questions. Then I came to the company for on-site interview. I met with at least 5 engineers/manager, each have detail technology questions. Most are easy but someone brought out two pages of real code, seemly from the real product, and asked me to detect any possible bugs. It is about multi-task embedded OS with mutual lock. The manager asked me to implement in C++ on hash table.