Preprocessor Macro Expander

About

This project is a C program that processes a source code file (myprog.c) and expands #define macros, replacing occurrences of defined macros with their corresponding values. The program reads the file, identifies #define directives, and substitutes macro occurrences while maintaining the structure of the original file.

Features

• Reads a C source file (myprog.c).
• Identifies and stores #define macro definitions.
• Replaces all instances of macros with their defined values.
• Removes #define directives from the final output.
• Writes the processed code into a temporary file without macros.

How It Works

1. The program reads myprog.c and counts characters, lines, and longest line length.
2. It extracts #define macro definitions and stores them in separate buffers.
3. It creates a temporary file (temp.txt), replacing occurrences of macros with their values.
4. It removes all #define directives from the processed file.
5. The final output is written into temp2.txt and then restored to temp.txt before cleanup.

Requirements

• GCC Compiler
• C Standard Library (stdio.h, stdlib.h, string.h)

Compilation

To compile the program, run:

gcc -o macro_expander macro_expander.c

Usage

Run the program with:

./macro_expander

Ensure myprog.c exists in the same directory before execution.

Limitations

• Assumes #define macros follow a simple format.
• Does not handle multi-line macro definitions.
• Limited to #define replacement without parameterized macros.

License

This project is open-source and licensed under the MIT License. Contributions and improvements are welcome!

Author

Akash Sureshbhai Khanpara