[PD] netsend/netreceive questions ...

[Christof Ressi]

> I believe what happens is that mrpeach/net objects output each incoming chunk as a whole, or spoken from Pd view as list.
...
> iemnet's tcp* objects make this nature of TCP explicitly clear by
> outputting only single bytes, a.k.a stream of bytes.

You're absolutely right!

The help patch for mrpeach/tcpsend is really misleading because instead of [packOSC] it should rather mention [packOSCstream] (which is just an abstraction with [packOSC]+[slipenc]). It really managed to fool me into thinking that OSC + TCP is possible... although via localhost, I have to send OSC messages with more than 4000 float args to make it break. Anyway, I think I never actually used OSC + TCP without SLIP encoding in a project (otherwise I would have gotten occasional errors from [unpackOSC]) - and I certainly won't in the future :-).

> Gesendet: Mittwoch, 22. Februar 2017 um 23:11 Uhr
> Von: "Roman Haefeli" <reduzent at gmail.com>
> An: pd-list at lists.iem.at
> Betreff: Re: [PD] netsend/netreceive questions ...
>
> On Mit, 2017-02-22 at 18:56 +0100, Christof Ressi wrote:
> > 
> > > 
> > > 
> > > No, that's not a workable solution, even if it might seem to work
> > > for
> > > you. Since TCP is a stream oriented protocol and doesn't have any
> > > notion of packets, you need to implement some mechanism to delimit
> > > packets.
> > That's correct! I was just wondering, why I thought that would
> > work... I checked again and it turned out I was using
> > [mrpeach/tcpsend] and [mrpeach/tcpreceive]. With these objects I can
> > reliably send and receive OSC data. The help file explicitly states:
> > 
> > "tcpsend sends bytes over a tcp connection.
> > Used in conjunction with packOSC will send OSC over tcp".
> > 
> > OTOH, the iemnet objects with the same name don't support that. And
> > [netsend -b]/[netreceive -b] don't either, as you correctly pointed
> > out. I guess, the mrpeach tcp objects use some kind of protocol
> > internally to delimit messages... interesting...
> I don't think so. Even with a TCP connection being a stream, TCP is
> transported by IP packets. I believe what happens is that mrpeach/net
> objects output each incoming chunk as a whole, or spoken from Pd view
> as list. There is no guarantee whatsoever that those chunks are
> received in the same configuration as they have been sent. While it
> seems to work when you test on localhost, it might miserably fail with
> some other network setup. TCP only guarantees that byte x[n+1] follows
> byte x[n], but not that one chunk of data is also received as one chunk
> of data. It might be split into two chunks, or two chunks are received
> as one. 
> iemnet's tcp* objects make this nature of TCP explicitly clear by
> outputting only single bytes, a.k.a stream of bytes.
> 
> Roman_______________________________________________
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