# Concurrency and async / await { #concurrency-and-async-await }

Details about the `async def` syntax for *path operation functions* and some background about asynchronous code, concurrency, and parallelism.

## In a hurry? { #in-a-hurry }

<abbr title="too long; didn't read"><strong>TL;DR:</strong></abbr>

If you are using third party libraries that tell you to call them with `await`, like:

```Python
results = await some_library()
```

    writePing()
    awaitPong()
  }

  /** For testing: sends a ping to be awaited with [awaitPong]. */
  @Throws(InterruptedException::class)
  fun writePing() {
    withLock {
      awaitPingsSent++
    }

    // 0x4f 0x4b 0x6f 0x6b is "OKok".
    writePing(false, AWAIT_PING, 0x4f4b6f6b)
  }

  /** For testing: awaits a pong. */
  @Throws(InterruptedException::class)
  fun awaitPong() {

   * non-satisfied before reacquiring the lock, and that other thread takes over the responsibility
   * of signaling the next waiter.
   *
   * Unlike the underlying Condition, if we are not careful, an interrupt *can* cause a signal to be
   * lost, because the signal may be sent to a condition whose sole waiter has just been
   * interrupted.
   *

Detalles sobre la sintaxis `async def` para *path operation functions* y algunos antecedentes sobre el código asíncrono, la concurrencia y el paralelismo.

## ¿Con prisa? { #in-a-hurry }

<abbr title="too long; didn't read - demasiado largo; no lo leí"><strong>TL;DR:</strong></abbr>

Si estás usando paquetes de terceros que te dicen que los llames con `await`, como:

```Python

                    response = await f(request)
                await response(scope, receive, send)
                # Continues customization
                response_awaited = True
            if not response_awaited:
                raise FastAPIError(
                    "Response not awaited. There's a high chance that the "

# Nebenläufigkeit und async / await { #concurrency-and-async-await }

Details zur `async def`-Syntax für *Pfadoperation-Funktionen* und Hintergrundinformationen zu asynchronem Code, Nebenläufigkeit und Parallelität.

## In Eile? { #in-a-hurry }

<abbr title="too long; didn't read - Zu lang; nicht gelesen"><strong>TL;DR:</strong></abbr>

Wenn Sie Bibliotheken von Dritten verwenden, die mit `await` aufgerufen werden müssen, wie zum Beispiel:

```Python

### SIG Cluster Lifecycle

For 1.13 SIG Cluster Lifecycle is pleased to announce the long awaited promotion of kubeadm to stable GA, and the promotion of kubeadm’s configuration API to `v1beta1`.

  volatile @Nullable Waiter waitersField;

  /** Non-volatile write of the thread to the {@link Waiter#thread} field. */
  private static void putThread(Waiter waiter, Thread newValue) {
    ATOMIC_HELPER.putThread(waiter, newValue);
  }

  /** Non-volatile write of the waiter to the {@link Waiter#next} field. */
  private static void putNext(Waiter waiter, @Nullable Waiter newValue) {

    waiter2.join();
  }

  public void testRemoveWaiter_polling() throws Exception {
    AbstractFuture<String> future = new AbstractFuture<String>() {};
    WaiterThread waiter = new WaiterThread(future);
    waiter.start();
    waiter.awaitWaiting();
    PollingThread poller = new PollingThread(future);
    poller.start();
    PollingThread poller2 = new PollingThread(future);
    poller2.start();

                        // Ignore
                    }
                }
            });

            waiter.start();
            Thread.sleep(50); // Give waiter time to start

            response.received();

            assertTrue(latch.await(500, TimeUnit.MILLISECONDS));
            assertTrue(response.isReceived());
        }

        @Test