}
  }

  // TODO GET preferred order - with tests to confirm this
  // 1. successful fresh cached GET response
  // 2. unsuccessful (404, 500) fresh cached GET response
  // 3. successful network response
  // 4. successful stale cached GET response
  // 5. unsuccessful response
  @Test
  fun usesCache() {
    val cache = Cache(cacheFs, "cache".toPath(), (100 * 1024).toLong())

    int NT_STATUS_NOTIFY_ENUM_DIR = 0x0000010C;
    /** The data was too large to fit into the specified buffer */
    int NT_STATUS_BUFFER_OVERFLOW = 0x80000005;
    /** The requested operation was unsuccessful */
    int NT_STATUS_UNSUCCESSFUL = 0xC0000001;
    /** The requested operation is not implemented */
    int NT_STATUS_NOT_IMPLEMENTED = 0xC0000002;
    /** The specified information class is invalid */

    serverIpv4.close()
    serverIpv6.close()

    val call = client.newCall(Request(url))
    assertFailsWith<IOException> {
      call.execute()
    }

    // In the process we made two unsuccessful connection attempts.
    assertThat(eventRecorder.recordedEventTypes().filter { it == ConnectStart::class }).hasSize(2)
    assertThat(eventRecorder.recordedEventTypes().filter { it == ConnectFailed::class }).hasSize(2)
  }

     * block is automatically generated from the ntstatus package.
     */

    /** The operation completed successfully */
    int NT_STATUS_SUCCESS = 0x00000000;
    /** The requested operation was unsuccessful */
    int NT_STATUS_UNSUCCESSFUL = 0xC0000001;
    /** The requested operation is not implemented */
    int NT_STATUS_NOT_IMPLEMENTED = 0xC0000002;
    /** The specified information class is invalid */

	}
	if err := b.UnreadByte(); err == nil {
		t.Fatal("UnreadByte after ReadByte at EOF: got no error")
	}

	// check not at EOF
	b.WriteString("abcdefghijklmnopqrstuvwxyz")

	// after unsuccessful read
	if n, err := b.Read(nil); n != 0 || err != nil {
		t.Fatalf("Read(nil) = %d,%v; want 0,nil", n, err)
	}
	if err := b.UnreadByte(); err == nil {
		t.Fatal("UnreadByte after Read(nil): got no error")
	}

</p>

<p class="rule">
A successful call to <code>l.TryLock</code> (or <code>l.TryRLock</code>)
is equivalent to a call to <code>l.Lock</code> (or <code>l.RLock</code>).
An unsuccessful call has no synchronizing effect at all.
As far as the memory model is concerned,
<code>l.TryLock</code> (or <code>l.TryRLock</code>)
may be considered to be able to return false
even when the mutex <i>l</i> is unlocked.