How do I turn a string into a `CPointer<ByteVar...

# kotlin-native

[martmists]

How do I turn a string into a CPointer<ByteVar>? I only see .cstr documented but that turns it into a CValues<ByteVar>

[mbonnin]

I don't think you can ? My current mental model is that CPointer is for something that lives on the heap (has reference semantics) while CValues has value semantics (might be a const string or something else, not sure)

[mbonnin]

You can alloc a CPointer and memcpy to it though:

val src = "Hello".cstr
      val dst = allocArray<ByteVar>(src.size)
      memcpy(dst, src, src.size.convert())

(don't take this as gospel, it might very well be wrong about size, terminating zero and all that kind of thingies)

[Dominaezzz]

memScoped { yourFunction("The string".cstr.ptr) } . Haven't done native in a while but this is a shortcut iirc.

[martmists]

@Dominaezzz that one won't work since I need to return it, but why would I use that over, say, a StableRef (which I found as alternative)

[Dominaezzz]

Stable ref? How does that help you?

[martmists]

It allows me to get a pointer from a variable rather than having to allocate the string again and copy it into there which would lead to a memory leak

[Dominaezzz]

The pointer you get from stable ref is opaque. It doesn't point to any data you're allowed to touch. It's meant to be used for callbacks, like a C handle for Kotlin objects. Also they need to be released so you'll leak either way.