Summary
In this chapter, we started to discuss Unix and how it is interrelated with C. Even in non-Unix operating systems, you see some traces of a similar design to Unix systems.
As part of this chapter, we went through the history of the early 1970s and explained how Unix appeared from Multics and how C was derived from the B programming language. After that, we talked about the Unix architecture, an onion-like architecture that consists of four layers: user applications, the shell, the kernel, and hardware.
We briefly went over the various layers in the Unix onion model and provided detailed explanations of the shell layer. We introduced the C standard library and how it is used through POSIX and SUS standards to give programmers the ability to write programs that can be built on various Unix systems.
In the second part of our look into Unix, Chapter 11, System Calls and Kernels, we will continue our discussion about Unix and its architecture, and we will provide explanations...