Hi Günter,

Thanks for answering, I expected that you would mention this aspect.

I don't know about OSC, but from your description it sounds like it basically 
is a binary protocol, where some sequences of bytes are to be interpreted as 
ASCII encoded strings.

I would just work on binary streams and do the encoding/decoding as needed.

ASCII is trivial, you can either do:

ZnCharacterEncoder ascii encodeString: 'OSC'

or

'OSC' asByteArray

And the inverse is either

ZnCharacterEncoder ascii decodeBytes: #[79 83 67].

or

#[79 83 67] asString.

The OSC spec says:

OSC-string
A sequence of non-null ASCII characters followed by a null, followed by 0-3 
additional null characters to make the total number of bits a multiple of 32.

One approach could be:

#writeOSCString: string on: stream

  stream nextPutAll: (ZnCharacterEncoder ascii encodeString: string).
  stream nextPut: 0.
  (string size + 1) // 4 timesRepeat: [ stream nextPut: 0 ]

#readOSCStringFrom: stream

  | string |
  string := ByteArray streamContents: [ :out |
    [ stream peekFor: 0 ] whileFalse: [ out nextPut: stream next ] ].
  (string size + 1) // 4 timesRepeat: [ stream next ].
  ^ ZnCharacterEncoder ascii decodeBytes: string

My point being that you probably don't need RWTextOrBinaryStream at all.

Of course, if you ported existing code and don't want to change it much, your 
solution is acceptable.

Sven

> On 21 May 2021, at 15:39, Günter Khyo <e...@chello.at> wrote:
> 
> A RWTextOrBinaryStream instance can operate in binary or ascii mode, the mode 
> can be switched at any time by sending ascii or binary, and some methods are 
> mode-sensitive, e.g., contents will respond with a ByteArray in binary mode 
> and a ByteString in ascii mode. (OSC uses ASCII encoding for addresses and 
> strings, and binary formats for numbers and blobs.)
> 
> The OSC testcases and the parser rely on this behavior. 
> 
> On 5/21/21 3:00 PM, Sven Van Caekenberghe wrote:
>> 
>>> On 21 May 2021, at 14:02, Günter Khyo via Pharo-dev 
>>> <pharo-dev@lists.pharo.org>
>>>  wrote:
>>> 
>>> Hi,
>>> 
>>> I have ported the Open Sound Control package to Pharo 9.0. Since the 
>>> Catalog Browser is marked as legacy, I was wondering how to submit the 
>>> patch. Is there a git repository? I attached the fileout to this email in 
>>> case anybody wants to take a look at the package or knows how/where to add 
>>> it to Pharo 9.0, 
>>> 
>>> Patch Note:
>>> 
>>> OSC relies on the removed RWTextOrBinaryStream class which has very 
>>> specific behavior that I could not emulate using the available stream and 
>>> codec classes, so I pulled in the class from Squeak 5, renamed it to 
>>> OSCStream and added it to the OSC package. This seemed to be the easiest 
>>> way to do it without changing the OSC implementation, but I welcome any 
>>> suggestions for a cleaner solution.
>>> 
>> I am curious, what was the specific behaviour that you could not emulate ?
>> 
>> 
>>> Günter
>>> 
>>> <OSC.st>
>>> 

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