A <code>nil</code> channel is never ready for communication.
</p>

<p>
A channel may be closed with the built-in function
<a href="#Close"><code>close</code></a>.
The multi-valued assignment form of the
<a href="#Receive_operator">receive operator</a>
reports whether a received value was sent before
the channel was closed.
</p>

<p>
A single channel may be used in

  // first client attaches to stdin, and then remains open and accepts data until the client disconnects,
  // at which time stdin is closed and remains closed until the container is restarted. If this
  // flag is false, a container processes that reads from stdin will never receive an EOF.
  // Default is false
  // +optional
  optional bool stdinOnce = 17;

- Apiserver add a new flag --goaway-chance which is the fraction of requests that will be closed gracefully(GOAWAY) to prevent HTTP/2 clients from getting stuck on a single apiserver. 
  After the connection closed(received GOAWAY), the client's other in-flight requests won't be affected, and the client will reconnect. 

- Fixes regression in logging spurious stack traces when proxied connections are closed by the backend ([#82588](https://github.com/kubernetes/kubernetes/pull/82588), [@liggitt](https://github.com/liggitt))

- `DelayingQueue.ShutDown()` can now be invoked multiple times without causing a closed channel panic. ([#77170](https://github.com/kubernetes/kubernetes/pull/77170), [@smarterclayton](https://github.com/smarterclayton))

- Fixed admission metrics in seconds. ([#72343](https://github.com/kubernetes/kubernetes/pull/72343), [@danielqsj](https://github.com/danielqsj))
- When a watch is closed by an HTTP2 load balancer and we are told to go away, skip printing the message to stderr by default.

* GCE: provide an option to disable docker's live-restore on COS/ubuntu ([#55260](https://github.com/kubernetes/kubernetes/pull/55260), [@yujuhong](https://github.com/yujuhong))
* Fix kube-proxy hang due to panic when requesting a closed healthcheck. ([#46450](https://github.com/kubernetes/kubernetes/pull/46450), [@MrHohn](https://github.com/MrHohn))

- Fixed bug where CSI migration doesn't count inline volumes for attach limit. ([#107787](https://github.com/kubernetes/kubernetes/pull/107787), [@Jiawei0227](https://github.com/Jiawei0227))
- Fixed error "dbus: connection closed by user" after dbus daemon restarts. ([#110496](https://github.com/kubernetes/kubernetes/pull/110496), [@kolyshkin](https://github.com/kolyshkin))

   ([#123190](https://github.com/kubernetes/kubernetes/pull/123190), [@padlar](https://github.com/padlar))
- Allowed scheduling framework plugins that implement `io.Closer` to be gracefully closed.
   ([#122498](https://github.com/kubernetes/kubernetes/pull/122498), [@Gekko0114](https://github.com/Gekko0114))
- Bumped cAdvisor to `v0.49.0`.

- Fix kubelet to not leak goroutines/intofiy watchers on an inactive connection if it's closed ([#67285](https://github.com/kubernetes/kubernetes/pull/67285), [@yujuhong](https://github.com/yujuhong))