Understanding the C Preprocessor

  • Introduction to the C preprocessor
  • Its role in processing source code before compilation
  • The importance of preprocessor directives

Features of the C Preprocessor

  • Overview of the build process
  • Preprocessor's role in creating expanded source code
  • Different preprocessor directives
  • Listing the directives to be covered

Macro Expansion

  • Explanation of macro definition using #define
  • Benefits of using macros for constants
  • Examples of macro templates and expansions
  • The importance of using capital letters for macros

Macros with Arguments

  • Introduction to macros with arguments
  • Example of a macro with arguments for area calculation
  • Importance of proper syntax
  • Example of a macro for checking if a character is a digit

Macros vs. Functions

  • Comparing macros and functions
  • Trade-offs between memory space and execution time
  • Situations where macros are preferred
  • Situations where functions are preferred

File Inclusion

  • Explanation of file inclusion using #include
  • Reasons for including external files
  • Commonly used header files and libraries
  • Different ways to write #include statements

Conditional Compilation

  • Use of #ifdef and #endif for conditional code inclusion
  • Practical applications, such as commenting out code
  • Making programs portable for different platforms
  • Using #ifndef as an alternative

#if and #elif Directives

  • Explaining the #if directive for conditional compilation
  • Using expressions to control code inclusion
  • Nested conditional compilation and simplification with #elif

Miscellaneous Directives

  • Brief introduction to #undef and #pragma
  • Mentioning that they are less commonly used
  • Possible use cases for these directives

#undef Directive

Explain the purpose and usage of the #undef directive in C programming.

#pragma Directive

Describe the various use cases of the #pragma directive, including #pragma startup, #pragma exit, and #pragma warn.

The C Program Build Process

Provide an overview of the steps involved in converting a C program into an executable form, with a focus on preprocessing, compilation, assembling, linking, and loading.

Preprocessing

Explain the role of preprocessing, how source code is expanded, and how it is stored in an intermediate file with a .i extension.

Compilation

Describe the compilation phase, where syntax errors and warnings are identified and how the source code is translated into equivalent assembly language.

Assembling

Discuss how the assembler translates assembly code into relocatable object code and what "relocatable" means in this context.

Linking

Explain the role of the linker in combining code and data sections from different object files and how it resolves addresses.

Loading

Describe the loading process and how the program is brought from the disk into memory for execution.

Binary File Formats

Explain the differences in binary file formats used by different operating systems, such as PE for Windows and ELF for Linux.

Summary

Summarize the key points of the presentation, including the benefits of preprocessor directives and an understanding of the C program build process.