*
     * We need to apply the settings and ack them atomically. This is because some HTTP/2
     * implementations (nghttp2) forbid peers from taking advantage of settings before they have
     * acknowledged! In particular, we shouldn't send frames that assume a new `initialWindowSize`
     * until we send the frame that acknowledges this new size.
     *

            esac
        then
            arg=$( cygpath --path --ignore --mixed "$arg" )
        fi
        # Roll the args list around exactly as many times as the number of
        # args, so each arg winds up back in the position where it started, but
        # possibly modified.
        #
        # NB: a `for` loop captures its iteration list before it begins, so

     *
     * * **Unreachable proxy servers.** A [ProxySelector] can be used to
     *   attempt multiple proxy servers in sequence, eventually falling back to a direct
     *   connection.
     *
     * Set this to false to avoid retrying requests when doing so is destructive. In this case the
     * calling application should do its own recovery of connectivity failures.

    `NullPointerException` crashes in `Deflater`.

 *  Fix: Don't crash after a web socket fails its connection upgrade. We incorrectly released
    the web socket's connections back to the pool before their resources were cleaned up.

 *  Fix: Don't infinite loop when a received web socket message has self-terminating compressed
    data.

   * Test to confirm that events are reported at the time they occur and no earlier and no later.
   * This inserts a bunch of synthetic 250 ms delays into both client and server and confirms that
   * the same delays make it back into the events.
   *
   * We've had bugs where we report an event when we request data rather than when the data actually
   * arrives. https://github.com/square/okhttp/issues/5578
   */

    type: Int,
    flags: Int,
  ): String {
    if (flags == 0) return ""
    when (type) {
      // Special case types that have 0 or 1 flag.
      TYPE_SETTINGS, TYPE_PING -> return if (flags == FLAG_ACK) "ACK" else BINARY[flags]
      TYPE_PRIORITY, TYPE_RST_STREAM, TYPE_GOAWAY, TYPE_WINDOW_UPDATE -> return BINARY[flags]
    }
    val result = if (flags < FLAGS.size) FLAGS[flags]!! else BINARY[flags]

By default, OkHttp will attempt a `MODERN_TLS` connection.  However by configuring the client connectionSpecs you can allow a fall back to `COMPATIBLE_TLS` connection if the modern configuration fails.

```java
OkHttpClient client = new OkHttpClient.Builder()
    .connectionSpecs(Arrays.asList(ConnectionSpec.MODERN_TLS, ConnectionSpec.COMPATIBLE_TLS))

      var low = 0
      var high = size
      var match: String? = null
      while (low < high) {
        var mid = (low + high) / 2
        // Search for a '\n' that marks the start of a value. Don't go back past the start of the
        // array.
        while (mid > -1 && this[mid] != '\n'.code.toByte()) {
          mid--
        }
        mid++

        // Now look for the ending '\n'.
        var end = 1

 * Events and sequences of events may be repeated for retries and follow-ups.
 *
 * All event methods must execute fast, without external locking, cannot throw exceptions, attempt
 * to mutate the event parameters, or be re-entrant back into the client. Any IO - writing to files
 * or network should be done asynchronously.
 */
abstract class EventListener {
  /**
   * Invoked as soon as a call is enqueued or executed by a client. In case of thread or stream

    assertThat(response.body.string()).isEqualTo("")
    server.takeRequest() // seed
    return server.takeRequest()
  }

  /**
   * For Last-Modified and Date headers, we should echo the date back in the exact format we were
   * served.
   */
  @Test
  fun retainServedDateFormat() {
    // Serve a response with a non-standard date format that OkHttp supports.