Two downloads at a time from a big list of downloads

Semipseudocode

import java.util.concurrent.Semaphore
// ...

const CONCURRENT_DOWNLOADS = 2
val queue = Sempahore(CONCURRENT_DOWNLOADS)

fun download(url: URL) {
  // .. do the download
  queue.release()
}
  
suspend fun gettem() = coroutineScope {
  val list = repo.getList()
  list.forEach {
    queue.acquire()
    launch {
      download(it.url)
    }
  }
}