Book Image

Extreme C

By : Kamran Amini
5 (1)
Book Image

Extreme C

5 (1)
By: Kamran Amini

Overview of this book

There’s a lot more to C than knowing the language syntax. The industry looks for developers with a rigorous, scientific understanding of the principles and practices. Extreme C will teach you to use C’s advanced low-level power to write effective, efficient systems. This intensive, practical guide will help you become an expert C programmer. Building on your existing C knowledge, you will master preprocessor directives, macros, conditional compilation, pointers, and much more. You will gain new insight into algorithm design, functions, and structures. You will discover how C helps you squeeze maximum performance out of critical, resource-constrained applications. C still plays a critical role in 21st-century programming, remaining the core language for precision engineering, aviations, space research, and more. This book shows how C works with Unix, how to implement OO principles in C, and fully covers multi-processing. In Extreme C, Amini encourages you to think, question, apply, and experiment for yourself. The book is essential for anybody who wants to take their C to the next level.
Table of Contents (23 chapters)

Kernel interface to shell ring

In the previous section, we explained that the shell ring in a Unix system exposes the interfaces defined in the SUS or POSIX standard. There are mainly two ways to invoke a certain logic in the shell ring, either through the libc or using shell utility programs. A user application should either get linked with libc libraries to execute shell routines, or it should execute an existing utility program that's available in the system.

Note that the existing utility programs are themselves using the libc libraries. Therefore, we can generalize and state that all shell routines can be found in libc libraries. This gives even more importance to standard C libraries. If you want to create a new Unix system from scratch, you must write your own libc after having the kernel up and ready.

If you have followed the flow of this book and have read the previous chapters, you'll see that pieces of the puzzle are coming together. We needed to have a compilation...