Summary
This chapter covers the role of the C preprocessor and its directives (starting with #) that perform purely text-based transformations—such as including files, defining constants, and conditionally compiling code—before actual compilation.

General domain of usage
C software compilation and build management

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To take advantage of the capabilities of preprocessing, the C language uses special instructions - **directives**.

Each directive begins with a symbolic hash **#**. You have already encountered preprocessor directives when connecting the built-in standard input/output library (stdio.h).

Preprocessor directives allow you to **include files**, **define constants**, and **conditionally compile parts of the code**. They are essential for organizing and optimizing the compilation process.

What symbol is used for preprocessor directive?

You will discover the secret of compilation using the console and learn how to compile programs manually. Get to know the preprocessor better and learn how to create your own macros of varying complexity. Take your programming skills to the next level with a set of preprocessor directives that will make your programs more understandable, convenient, and make compilation flexible!

Dive into the compilation process, see how to do compilation yourself using terminal commands.

Get acquainted with macros and their varieties. You will learn how to create/delete object and functional macros, and also master new tricks for working with strings .

Create conditions for different compilation scenarios using conditional preprocessor directives.

Dive into advanced preprocessor capabilities that allow you to precisely control compilation, interact with the compiler, and create flexible, manageable code using directives and built-in macros.

Role of the Preprocessor

Role of the Preprocessor