I was reading "Operating Systems Design and Implementation" by Andrew S. Tanenbaum. It has Source code of MINIX when approaching the back of the book. I know C programming and have also studied the subject of Operating Systems, but still I was not able to understand the source code. Very few lines were such which could be understood.
I found many new libraries included over there. These libraries are not taught the syllabus of my university. Also, when asked teachers of this, even they don't understand the code. So, where can whole C programming be learnt, with all of its libraries? Because university doesn't go in depths.
In a nut shell, how can we learn C programming or any other programming language to such a depth, that by just looking at any code, one can tell what is the code gonna do.