It was telephonic round in which interviewer asked about basic c questions like, Structure and union, compilation process, storage class, difference between calloc and malloc, dynamic memory allocation etc...after they asked question on linux like, what is process, what are ipc mechanism, how two processes will communication using ipc, message queue etc...after again some questions on TCP/IP like what is socket, step for TCP/IP communication, udp and tcp difference....only want to tell that study the basic concepts with good understanding.