RE: Channel concept instead of simple Files

[acken@informatik.uni-kl.de]

>  Date: Wed, 10 Jan 96 08:08:27 EST
>  From: Mike Griebling <grieblm@trt.allied.com>
>  
>  Let's do it the Oberon/F way.  I'm all for compatibility with an existing
>  implementation.
>  
>  
I like your enthusiasm.  But I checked the WinOberon/F version I got
(1.0), and their Files module is basically the one that Sander
presented.  O/F doesn't offer the kind of flexibility I'd like to see.
Does anyone know if there is a more recent version of O/F with an
enhanced IO concept?

The text Guy quoted previously has one good point: It identifies three
levels of abstraction in the IO process.  

  chunk of data, identified by a locator
      |  (eg file, memory block, pipe, tcp/ip)
      |
      |
  basic reader/writer operating on bytes
      | (offer SetPos, ReadByte, ReadBytes, WriteByte, WriteBytes)
      |
      |
  reader/writer to translate high level data into byte stream
        (eg. binary reader/writer, text rd/wr, see Sander's Files module)

This concept allows multiple readers and writers on one piece of data
(just like the Oberon System does it on files), and allows to
distinguish between the simple access layer that doesn't know a thing
about the byte stream being read or written, and the interpretation
layer that transforms some bytes into useful data.

-- Michael