val pooled1 = planReusePooledConnection()
    if (pooled1 != null) return pooled1

    // Attempt a deferred plan before new routes.
    if (deferredPlans.isNotEmpty()) return deferredPlans.removeFirst()

    // Do blocking calls to plan a route for a new connection.
    val connect = planConnect()

    // Now that we have a set of IP addresses, make another attempt at getting a connection from

configured to fall back for broad connectivity.

Using OkHttp is easy. Its request/response API is designed with fluent builders and immutability. It
supports both synchronous blocking calls and async calls with callbacks.

A well behaved user agent
-------------------------

OkHttp follows modern HTTP specifications such as

   * call this without consuming the complete response body, any remaining bytes in the response
   * body will be discarded before trailers are returned.
   *
   * If [Call.cancel] is called while this is blocking, this call will immediately throw.
   *
   * @throws IllegalStateException if the response is closed.
   * @throws IOException if the trailers cannot be loaded, such as if the network connection is
   *     dropped.

      return result;
    }

    /**
     * Following the contract of {@link AbstractQueuedSynchronizer} we create a private subclass to
     * hold the synchronizer. This synchronizer is used to implement the blocking and waiting calls
     * as well as to handle state changes in a thread-safe manner. The current state of the future
     * is held in the Sync state, and the lock is released whenever the state changes to {@link

   */
  public static final byte SYN = 22;

  /**
   * End of Transmission Block: A communication control character used to indicate the end of a
   * block of data for communication purposes. ETB is used for blocking data where the block
   * structure is not necessarily related to the processing format.
   *
   * @since 8.0
   */
  public static final byte ETB = 23;

  /**

 *
 * @author Anthony Zana
 * @since 10.0
 */
@GwtCompatible
public final class Uninterruptibles {

  // Implementation Note: As of 3-7-11, the logic for each blocking/timeout
  // methods is identical, save for method being invoked.

  /** Invokes {@code latch.}{@link CountDownLatch#await() await()} uninterruptibly. */
  @J2ktIncompatible
  @GwtIncompatible // concurrency

        }
        curr = succ;
      }
      break;
    }
  }

  // A heuristic for timed gets. If the remaining timeout is less than this, spin instead of
  // blocking. This value is what AbstractQueuedSynchronizer uses.
  private static final long SPIN_THRESHOLD_NANOS = 1000L;

  @VisibleForTesting
  static String atomicHelperTypeForTest() {

requests, responses, headers, and calls. It uses modern Java patterns like
immutability and chained builders. The API now offers asynchronous callbacks
in addition to synchronous blocking calls.

#### API Changes

 *  **New Request and Response types,** each with their own builder. There's also
    a `RequestBody` class to write the request body to the network and a

        }
        curr = succ;
      }
      break;
    }
  }

  // A heuristic for timed gets. If the remaining timeout is less than this, spin instead of
  // blocking. This value is what AbstractQueuedSynchronizer uses.
  private static final long SPIN_THRESHOLD_NANOS = 1000L;

  @VisibleForTesting
  static String atomicHelperTypeForTest() {

/// warning

Você pode provavelmente pular isso.

Esses são detalhes muito técnicos de como **FastAPI** funciona por baixo do capô.

Se você tem certo conhecimento técnico (corrotinas, threads, blocking etc) e está curioso sobre como o FastAPI controla o `async def` vs normal `def`, vá em frente.

///

### Funções de operação de rota