CODE EXAMPLE FOR SWIFT

rust How to pass out parameter to function from Swift FFI

// Create storage
var content: UnsafeMutablePointer<CChar>? // Could be NULL, so Optional
var length: Int32 = 0
var capacity: Int32 = 0

// Pass as references
do_something(&content, &length, &capacity)

// Copy the data
let data = Array(UnsafeRawBufferPointer(start: content, count: Int(length)))