if n == 0 && err == nil && fd.ZeroReadIsEOF {
		return io.EOF
	}
	return err
}

// Shutdown wraps syscall.Shutdown.
func (fd *FD) Shutdown(how int) error {
	if err := fd.incref(); err != nil {
		return err
	}
	defer fd.decref()
	return syscall.Shutdown(fd.Sysfd, how)
}

// Fchown wraps syscall.Fchown.
func (fd *FD) Fchown(uid, gid int) error {
	if err := fd.incref(); err != nil {

	e.eventRecorder.Eventf(object, eventtype, reason, messageFmt, args...)
}

// Shutdown terminates the event recorder. This must be called upon completion of writing events, and events should not be
// written once terminated.
func (e *EventRecorder) Shutdown() {
	e.eventBroadcaster.Shutdown()

   * message buffer (16 MiB) will be rejected and trigger a [graceful shutdown][close] of this web
   * socket. This method returns false in that case, and in any other case where this web socket is
   * closing, closed, or canceled.
   *
   * This method returns immediately.
   */
  fun send(bytes: ByteString): Boolean

  /**
   * Attempts to initiate a graceful shutdown of this web socket. Any already-enqueued messages will

// Returned is a shutdown function that should be called to ensure graceful shutdown.
func Initialize() (func(), error) {
	exp, err := newExporter()
	if err != nil {
		return nil, err
	}
	tp := trace.NewTracerProvider(
		trace.WithBatcher(exp),
		trace.WithResource(newResource()),
	)
	otel.SetTracerProvider(tp)
	return func() {
		if err := tp.Shutdown(context.Background()); err != nil {

# Routes
# Home page
GET     /                           controllers.Application.index

GET     /shutdown                   controllers.Application.shutdown

# Map static resources from the /public folder to the /assets URL path

# Testing Events: startup - shutdown

When you need your event handlers (`startup` and `shutdown`) to run in your tests, you can use the `TestClient` with a `with` statement:

```Python hl_lines="9-12  20-24"
{!../../../docs_src/app_testing/tutorial003.py!}

	WaitForCacheSync(stopCh <-chan struct{}) bool

	// Shutdown marks a factory as shutting down. At that point no new
	// informers can be started anymore and Start will return without
	// doing anything.
	//
	// In addition, Shutdown blocks until all goroutines have terminated. For that
	// to happen, the close channel(s) that they were started with must be closed,
	// either before Shutdown gets called or while it is waiting.
	//

하나 이상의 이벤트 핸들러 함수를 추가할 수도 있습니다.

그리고 응용 프로그램은 모든 `startup` 이벤트 핸들러가 완료될 때까지 요청을 받지 않습니다.

## `shutdown` 이벤트

응용 프로그램이 종료될 때 실행하려는 함수를 추가하려면 `"shutdown"` 이벤트로 선언합니다:

```Python hl_lines="6"
{!../../../docs_src/events/tutorial002.py!}
```

이 예제에서 `shutdown` 이벤트 핸들러 함수는 `"Application shutdown"`이라는 텍스트가 적힌 `log.txt` 파일을 추가할 것입니다.

!!! info "정보"

本例中，`startup` 事件处理器函数为项目数据库（只是**字典**）提供了一些初始值。

**FastAPI** 支持多个事件处理器函数。

只有所有 `startup` 事件处理器运行完毕，**FastAPI** 应用才开始接收请求。

## `shutdown` 事件

使用 `shutdown` 事件声明 `app` 关闭时运行的函数：

```Python hl_lines="6"
{!../../../docs_src/events/tutorial002.py!}
```

此处，`shutdown` 事件处理器函数在 `log.txt` 中写入一行文本 `Application shutdown`。

!!! info "说明"

    `open()` 函数中，`mode="a"` 指的是**追加**。因此这行文本会添加在文件已有内容之后，不会覆盖之前的内容。

!!! tip "提示"

	runtime.SetFinalizer(fd, nil)
	return fd.pfd.Close()
}

func (fd *netFD) shutdown(how int) error {
	err := fd.pfd.Shutdown(how)
	runtime.KeepAlive(fd)
	return wrapSyscallError("shutdown", err)
}

func (fd *netFD) closeRead() error {
	return fd.shutdown(syscall.SHUT_RD)
}

func (fd *netFD) closeWrite() error {
	return fd.shutdown(syscall.SHUT_WR)
}

func (fd *netFD) Read(p []byte) (n int, err error) {