I had a phone interview on simple C and C++ . The interviewer basically looked into if I know wat i am talking. After that I had an online test..They sent me a ssample program and wanted me to mail it in 30 minutes. It was on reversing the bits of a number. I was invited for an on site interview . The interview went daylong...may be 5 in total (including lunch interview). It was on C, C++ and data structures and OS concepts. I am not a CS major and all though I kept OS on my resume, I dont know much abt it and I didnt perform well in 2 interviews.. Although the rest of the interviews were good. But the interview was not tough at all. Know all that u keep on ur resume.