Bind and call a C function

A package imports Interop.C and Interop.Boundary, then declares a binding known at compile time at module level:

use Interop.C
use Interop.Boundary

let write = C.function<
    func(int32, C.Pointer<uint8>, C.Size) C.SignedSize
>(
    library:Boundary.System,
    name:"write"
)

System is a provider declared by the package for every supported target. This let creates no mutable global state and runs no initializer. C.function applies the target's C calling convention.

The name remains the one documented by the API, here write. The selected provider supplies link entries without exposing them in the public Silex API.

Call it like an ordinary function

func write_text(text:str) C.SignedSize {
    return write(
        1,
        C.pointer(text),
        C.byte_count(text)
    )
}

The raw result follows the C contract. The binding must handle partial writes, system errors, and their conversion to its public error type.

A C function without a result uses void. Calling it as a statement creates no hidden Silex value. Unsigned byte parameters and results use exactly uint8; declaring an eight-bit C Boolean result as uint32 violates the ABI.

The accepted surface remains deliberately narrow: explicitly sized integers and floats, C.Pointer<T>, C.MutablePointer<T>, and void returns. Memory details are grouped in direct exchanges.

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