cangjie-cffi

You can declare external C functions in Cangjie using foreign declarations with optional @C qualifiers, then invoke them inside unsafe blocks. This standardizes cross-language calls and reduces boilerplate when integrating existing C APIs.

Memory management for C pointers in Cangjie involves allocating and freeing native memory via LibC. You use CPointer<T> and CString types to safely handle native resources and structured data across the language boundary.

Yes, you can define function pointers with CFunc and pass them as callbacks to C code. This mechanism supports bidirectional communication, allowing C libraries to invoke Cangjie functions through standardized foreign function interfaces.

You pass inout parameters to C functions by automatically passing their addresses to the native code. This allows bidirectional data flow, enabling C functions to modify Cangjie variables directly through pointer references.

Yes, unsafe blocks are required when invoking foreign C functions in Cangjie. Because C code operates outside Cangjie's safety guarantees, unsafe blocks explicitly mark the boundary where memory and pointer operations need manual validation.

The best way to map C structs is using the @C qualifier on struct definitions with CType constraints. This ensures the memory layout matches the C ABI, allowing safe passage of structured data between Cangjie and C code.