A coroutine function that suspends until a shutdown is requested

await_shutdown.kt

import kotlin.concurrent.thread
import kotlin.coroutines.resume
import kotlin.coroutines.suspendCoroutine

suspend fun awaitShutdown() {
    suspendCoroutine<Unit> { c ->
        Runtime.getRuntime().addShutdownHook(thread(start = false) {
            c.resume(Unit)
        })
    }
}