fun connectionPreface() {
    this.withLock {
      if (closed) throw IOException("closed")
      if (!client) return // Nothing to write; servers don't send connection headers!
      if (logger.isLoggable(FINE)) {
        logger.fine(format(">> CONNECTION ${CONNECTION_PREFACE.hex()}"))
      }
      sink.write(CONNECTION_PREFACE)
      sink.flush()
    }
  }

  /** Applies `peerSettings` and then sends a settings ACK. */

                    ReferenceAccess.READ -> arrayOf(KtFirSimpleNameReference(nameReferenceExpression, isRead = true))
                    ReferenceAccess.WRITE -> arrayOf(KtFirSimpleNameReference(nameReferenceExpression, isRead = false))
                    ReferenceAccess.READ_WRITE -> arrayOf(
                        KtFirSimpleNameReference(nameReferenceExpression, isRead = true),

    client.webSocket!!.close(1000, "Hello")
    server.processNextFrame()
    // Not closed until close reply is received.
    assertThat(client.closed).isFalse()

    // Manually write an invalid masked close frame.
    server.sink.write("888760b420bb635c68de0cd84f".decodeHex()).emit()
    client.processNextFrame() // Detects error, disconnects immediately since close already sent.
    client.webSocket!!.finishReader()

          throw ProtocolException("unexpected address: " + toSocket.localAddress)
        }

        // Write the reply.
        fromSink.writeByte(VERSION_5)
        fromSink.writeByte(REPLY_SUCCEEDED)
        fromSink.writeByte(0)
        fromSink.writeByte(ADDRESS_TYPE_IPV4)
        fromSink.write(localAddress)
        fromSink.writeShort(toSocket.localPort)
        fromSink.emit()

        readTimeout = checkDuration("duration", duration)
      }

    /**
     * Sets the default write timeout for new connections. A value of 0 means no timeout, otherwise
     * values must be between 1 and [Integer.MAX_VALUE] when converted to milliseconds.
     *
     * The write timeout is applied for individual write IO operations. The default value is 10
     * seconds.
     *
     * @see Sink.timeout
     */

    val dataLength = 16384
    // Write the mocking script.
    peer.sendFrame().settings(Settings())
    peer.acceptFrame() // ACK
    peer.acceptFrame() // SYN_STREAM
    peer.sendFrame().headers(false, 3, headerEntries("b", "banana"))
    peer.sendFrame().data(false, 3, Buffer().write(ByteArray(dataLength)), dataLength)
    peer.sendFrame().data(false, 3, Buffer().write(ByteArray(dataLength)), dataLength)

```

::: fastapi.UploadFile
    options:
        members:
            - file
            - filename
            - size
            - headers
            - content_type
            - read
            - write
            - seek

    setUp(parameters.first, parameters.second)
    cache.close()
    writeFile(getCleanFile("k1", 0), "A")
    writeFile(getCleanFile("k1", 1), "B")
    filesystem.write(journalFile) {
      writeUtf8(
        // No trailing newline.
        """
        |${DiskLruCache.MAGIC}
        |${DiskLruCache.VERSION_1}
        |100
        |2
        |
        |CLEAN k1 1 1

   */
  @JvmStatic
  fun fragmentBuffer(buffer: Buffer): Buffer {
    // Write each byte into a new buffer, then clone it so that the segments are shared.
    // Shared segments cannot be compacted so we'll get a long chain of short segments.
    val result = Buffer()
    while (!buffer.exhausted()) {
      val box = Buffer()
      box.write(buffer, 1)
      result.write(box.copy(), 1)
    }
    return result
  }

   *
   * Writes are subject to the write window of the stream and the connection. Until there is a
   * window sufficient to send [byteCount], the caller will block. For example, a user of
   * `HttpURLConnection` who flushes more bytes to the output stream than the connection's write
   * window will block.
   *