Effective C

9PREPROCESSOR

with Aaron Ballma

The preprocessor is the part of the C compiler that runs at an early phase of compilation and transforms the source code before it’s translated, such as inserting code from one file (typically a header file) into another (typically a source file). The preprocessor also allows you to specify that an identifier should be automatically substituted by a source code segment during macro expansion. In this chapter, you’ll learn how to use the preprocessor to include files, define object- and function-like macros, and conditionally include code based on implementation-specific features.

The Compilation Process

Let’s first ...