Christopher Preschern - Fluent C: Principles, Practices, and Patterns

by Christopher Preschern

Copyright 2023 Christopher Preschern. All rights reserved.

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978-1-492-09733-4

[LSI]

You picked up this book to move your programming skills one step forward. That is good, because youll definitely benefit from the hands-on knowledge provided in this book. If you have a lot of experience programming in C, youll learn the details of good design decisions and about their benefits and drawbacks. If you are fairly new to C programming, youll find guidance about design decisions, and youll see how these decisions are applied bit by bit to running code examples for building larger scale programs.

The book answers questions such as how to structure a C program, how to cope with error handling, or how to design flexible interfaces. As you learn more about C programming, questions often pop up, such as the following:

• Should I return any error information I have?

• Should I use the global variable errno to do that?

• Should I have few functions with many parameters or the other way around?

• How do I build a flexible interface?

• How can I build basic things like an iterator?

For object-oriented languages, most of these questions are answered to a great extent by the Gang of Four book Design Patterns: Elements of Reusable Object-Oriented Software by Erich Gamma, Richard Helm, Ralph Johnson, and John Vlissides (Prentice Hall, 1997). Design patterns provide a programmer with best practices on how objects should interact and which object owns which other kinds of objects. Also, design patterns show how such objects can be grouped together.

However, for procedural programming languages like C, most of these design patterns cannot be implemented in the way described by the Gang of Four. There are no native object-oriented mechanisms in C. It is possible to emulate inheritance or polymorphism in the C programming language, but that might not be the first choice, because such emulation makes things unfamiliar for programmers who are used to programming C and are not used to programming with object-oriented languages like C++ and using concepts like inheritance and polymorphism. Such programmers may want to stick to their native C programming style that they are used to. However, with the native C programming style, not all object-oriented design patterns guidance is usable, or at least the specific implementation of the idea presented in a design pattern is not provided for non-object-oriented programming languages.

And that is where we stand: we want to program in C, but we cannot directly use most of the knowledge documented in design patterns. This book shows how to bridge this gap and implement hands-on design knowledge for the C programming language.