: Study the headers of widely used C libraries like libgeos or MATLAB's C API to see how they handle stability and cross-language compatibility.
: Since C has a flat namespace, use consistent prefixes for all public functions and types (e.g., libname_create_context() ) to avoid naming collisions with other libraries. API Design for C
Creating a high-quality API for C requires balancing the language's low-level power with the need for safety, readability, and long-term stability. Unlike C++, C lacks built-in features like classes and namespaces, so designers must rely on disciplined conventions and patterns to provide a clean interface. Core Principles of C API Design : Study the headers of widely used C
: Return consistent error codes or use a "status" type for every function. Many successful C APIs return an integer status and use out-parameters for actual data. Unlike C++, C lacks built-in features like classes
: Avoid global variables within your library. Instead, pass a "context" or "handle" pointer to every function that needs to maintain state, which also helps with thread safety. Recommended Resources for Deep Dives
: Always provide paired functions for allocation and deallocation (e.g., _init() and _destroy() ). This ensures the user is responsible for the lifetime of objects they create.
: Keep internal implementation details hidden from the user by using opaque pointers (e.g., typedef struct my_object my_object_t; ). This allows you to change the struct's definition without breaking the binary compatibility of client code.
