unsafe

{

    byte[] message = UnicodeEncoding.Unicode.GetBytes("Here is some data.");

    IntPtr memIntPtr = Marshal.AllocHGlobal(message.Length);

    byte* memBytePtr = (byte*)memIntPtr.ToPointer();

    UnmanagedMemoryStream writeStream = new UnmanagedMemoryStream(memBytePtr, message.Length,

                                                                    message.Length, FileAccess.Write);

    writeStream.Write(message, 0, message.Length);

    writeStream.Close();

    UnmanagedMemoryStream readStream = new UnmanagedMemoryStream(memBytePtr, message.Length,

                                                                message.Length, FileAccess.Read);

    byte[] outMessage = new byte[message.Length];

    readStream.Read(outMessage, 0, message.Length);

    readStream.Close();

    Console.WriteLine(UnicodeEncoding.Unicode.GetString(outMessage));

    Marshal.FreeHGlobal(memIntPtr);

}

static void Main(string[] args)

{

    UnmanagedMemoryStream stream = WriteInStream();

    ReadFromStream(stream);

}

static UnmanagedMemoryStream WriteInStream()

{

    unsafe

    {

        byte[] message = UnicodeEncoding.Unicode.GetBytes("Here is some data.");

        IntPtr memIntPtr = Marshal.AllocHGlobal(message.Length);

        byte* memBytePtr = (byte*)memIntPtr.ToPointer();

        UnmanagedMemoryStream writeStream = new UnmanagedMemoryStream(memBytePtr, message.Length,

                                                                        message.Length, FileAccess.Write);

        writeStream.Write(message, 0, message.Length);

        Marshal.FreeHGlobal(memIntPtr);

        return writeStream;

    }

}

static void ReadFromStream(UnmanagedMemoryStream stream)

{

    unsafe

    {

        IntPtr memIntPtr = Marshal.AllocHGlobal((int)stream.Length);

        byte* memBytePtr = (byte*)memIntPtr.ToPointer();

        UnmanagedMemoryStream readStream = new UnmanagedMemoryStream(memBytePtr, stream.Length,

                                                                        stream.Length, FileAccess.Read);

        byte[] outMessage = new byte[stream.Length];

        readStream.Read(outMessage, 0, (int)stream.Length);

        readStream.Close();

        Console.WriteLine(UnicodeEncoding.Unicode.GetString(outMessage));

        Marshal.FreeHGlobal(memIntPtr);

    }

}

private UnmanagedMemoryStream GetPinnedBufferMemoryStream(byte[] buffer)

{

    Module module = typeof(UnmanagedMemoryStream).Module;

    Type pinnedBufferMemoryStreamType = module.GetTypes().

            Single(item => item.Name == "PinnedBufferMemoryStream");

    ConstructorInfo ctor = pinnedBufferMemoryStreamType.

                        GetConstructor(

                            BindingFlags.NonPublic | BindingFlags.Instance,

                            null,

                            new Type[] { typeof(byte[]) },

                            null);

    UnmanagedMemoryStream pinnedBufferMemoryStream =

        (UnmanagedMemoryStream)ctor.Invoke(new object[] { buffer });

    return pinnedBufferMemoryStream;

}