// Remove failed listings after 5 minutes.
		return time.Since(cache.lastUpdate) > 5*time.Minute
	}
	return true
}

// keepAlive will continuously update lastHandout until ctx is canceled.
func (m metacache) keepAlive(ctx context.Context, rpc *peerRESTClient) {
	// we intentionally operate on a copy of m, so we can update without locks.
	t := time.NewTicker(metacacheMaxClientWait / 10)
	defer t.Stop()

   * either from cancellation or because an input future has completed. If N futures are passed in,
   * and M delegates are cancelled, the remaining M input futures will be cancelled once N - M of
   * the input futures complete. If all the delegates are cancelled, all the input futures will be
   * too.
   *
   * @since 17.0
   */

      )
    call.cancel()
    assertFailsWith<IOException> {
      call.execute()
    }.also { expected ->
      assertThat(expected.message).isEqualTo("Canceled")
    }
    assertThat(eventRecorder.recordedEventTypes()).containsExactly(
      Canceled::class,
      CallStart::class,
      CallFailed::class,
    )
  }

  @Test
  fun cancelAsyncCall() {
    server.enqueue(
      MockResponse

 *
 *  * For asynchronous calls made with [Call.enqueue], an [IOException] is propagated to the caller
 *    indicating that the call was canceled. The interceptor's exception is delivered to the current
 *    thread's [uncaught exception handler][Thread.UncaughtExceptionHandler]. By default this

		r.writeCond = sync.NewCond(&r.mu)
	}
	return r
}

// WithCancel sets a context to cancel the ring buffer.
// When the context is canceled, the ring buffer will be closed with the context error.
// A goroutine will be started and run until the provided context is canceled.
func (r *RingBuffer) WithCancel(ctx context.Context) *RingBuffer {
	go func() {
		<-ctx.Done()
		r.CloseWithError(ctx.Err())
	}()
	return r
}

    override val call: Call,
    val ioe: IOException,
  ) : CallEvent() {
    override fun closes(event: CallEvent): Boolean = event is CallStart && call == event.call
  }

  data class Canceled(
    override val timestampNs: Long,
    override val call: Call,
  ) : CallEvent()

  data class RequestHeadersStart(
    override val timestampNs: Long,
    override val call: Call,
  ) : CallEvent()

)

// WalkDir will traverse a directory and return all entries found.
// On success a sorted meta cache stream will be returned.
// Metadata has data stripped, if any.
// The function tries to quit as fast as the context is canceled to avoid further drive IO
func (s *xlStorage) WalkDir(ctx context.Context, opts WalkDirOptions, wr io.Writer) (err error) {
	legacyFS := s.fsType != xfs && s.fsType != ext4

	s.RLock()
	legacy := s.formatLegacy

        ).setHeader("content-type", "text/event-stream")
        .build(),
    )
    listener.enqueueCancel() // Will cancel in onOpen().
    newEventSource()
    listener.assertOpen()
    listener.assertFailure("canceled")
  }

  @Test
  fun badContentType() {
    server.enqueue(
      MockResponse
        .Builder()
        .body(
          """
          |data: hey
          |
          |

			if errors.As(err, &cerr) {
				logger.FatalIf(err, "Unable to initialize the server")
			}

			// If context was canceled
			if errors.Is(err, context.Canceled) {
				logger.FatalIf(err, "Server startup canceled upon user request")
			}

			bootLogIf(GlobalContext, err)
		}

		if !globalServerCtxt.StrictS3Compat {

=== ":material-language-kotlin: Kotlin"
    ```kotlin
      private val executor = Executors.newScheduledThreadPool(1)
      private val client = OkHttpClient()

      fun run() {