For me the hiring process consisted of two interviews, one theoretical and one practical, both at the given at the company headquarters. The theoretical one was mostly with questions about C/C++ language and OOP in C++, but had also ~5 questions to write some code in order to resolve some tasks (reverse a string, converting 32bit color to 24bit color ...). It lasted 4-5 hours. I sit at a computer, I had internet, but I couldn't open some IDE to test code(not allowed). For the practical one I was put to modify the behavior of a game (written in C++) by changing some character skills / number of ammuntion of a weapons / others things like that from the game code (which was huge) and also to fix a bug. The bug was easy to reproduce and it would crash the game if you reproduced it correctly. The IDE was Visual Studio 20xx(forgot which was).

First a phone interview with HR people. Then they send you a knowledge test about different topics: C++, networks, algorithms, data structures, optimizations, design Patterns. You do it at home within a limited time. You send back your answers by mail. Finally, you get an interview at the company location with a manager, a developper and a HR person.