* responses coming back in. Typically interceptors add, remove, or transform headers on the request
 * or response.
 *
 * Implementations of this interface throw [IOException] to signal connectivity failures. This
 * includes both natural exceptions such as unreachable servers, as well as synthetic exceptions
 * when responses are of an unexpected type or cannot be decoded.
 *

  fun writeRequestHeaders(request: Request)

  /** Flush the request to the underlying socket. */
  @Throws(IOException::class)
  fun flushRequest()

  /** Flush the request to the underlying socket and signal no more bytes will be transmitted. */
  @Throws(IOException::class)
  fun finishRequest()

  /**
   * Parses bytes of a response header from an HTTP transport.
   *

      }
    }

    return isRunning
  }

  /** Used by [Call.execute] to signal it is in-flight. */
  internal fun executed(call: RealCall) =
    this.withLock {
      runningSyncCalls.add(call)
    }

  /** Used by [AsyncCall.run] to signal completion. */
  internal fun finished(call: AsyncCall) {
    call.callsPerHost.decrementAndGet()