I'm using a library designed around coroutines that also uses ktor so I also have ktor goodies to use. I noticed ktor provides "channels" (

ByteReadChannel

,

ByteWriteChannel

, what's the benefit of them? And what does the following mean?

Operations on this channel cannot be invoked concurrently.

when is a

ByteWriteChannel

more convenient than this?

val url = URL(...)
val targetDir = Path.of(...)

withContext(<http://Dispatchers.IO|Dispatchers.IO>) {
  url.openStream().use { stream ->
    Files.copy(stream, targetDir)
  }
}

are they just meant to be used to read and write in chunks without blocking everything else in a thread, and to yield it to other coroutines?

They are primitives to work with a stream of bytes in a non-blocking way.