C in 100 Seconds: Three Files One Program — Header Files | Episode 16
Header files separate declarations from definitions. The .h file declares what exists — function signatures. The .c file defines how they work.
#ifndef guards prevent double inclusion.
Three files: a header with two function declarations, an implementation with the bodies, and a main that calls them. Include with quotes for
your files, angle brackets for system libraries. Compile both .c files and the linker connects the calls to the implementations. That's how
real C projects are organized.
Student code: https://github.com/GoCelesteAI/c-in-1...
What You'll Learn:
• .h files declare, .c files define
• #ifndef / #define / #endif — include guards
• #include "quotes" for your files, brackets for system
• Compiling multiple .c files together
• The linker connects calls to implementations
Phase 1 Complete! Next: Episode 17 — Pointers (Phase 2: Pointers and Memory)
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