I wouldn't be able to do that off the top of my head because, in my C experience, I hardly ever read files. Everything we did was reading from or writing to me

I wouldn't be able to do that off the top of my head because, in my C experience, I hardly ever read files. Everything we did was reading from or writing to memory buffers. Furthermore, we did almost all system interactions through a platform-independent middleware interface. So, while I, for example, knew what a semaphore was and how to use it I could not remember the standard Linux interface for semaphores because we used the platform-independent API for ours. Expecting people to remember APIs off the top of their heads is ridiculous. Some do, some don't. The people who don't aren't lesser engineers just because they don't.