Final answer:
Preprocessors in C are tools that process code before compilation, and provide features like header file inclusion, macro definition, conditional compilation, and error message generation.
Step-by-step explanation:
Understanding Preprocessors in C
A preprocessor is a program that processes your source code before it is compiled by the compiler. In the context of C programming, the C preprocessor provides several useful facilities that help with code optimization and management. It allows programmers to include headers, define macros, conditional compilation, and line control. Some of the key facilities provided by the C preprocessor include:
- Header file inclusion: Using directives like #include, to insert the contents of one file into the source code.
- Macro definition and expansion: Using #define for creating constants and macros that can replace text during the preprocessing phase.
- Conditional compilation: Using #ifdef, #ifndef, #if, #else, and #endif to include or exclude parts of the code based on certain conditions.
- Compilation error messages: Using #error to generate error messages during compilation if a condition is met.
- Line control: Using #line to change the current line number and the filename as reported by the compiler in diagnostics.