[PD] tcpclient sending more than 1 send at once

Roman Haefeli reduzierer at yahoo.de
Mon Sep 8 23:01:12 CEST 2008

On Mon, 2008-09-08 at 20:41 +0000, Martin Peach wrote:
> Roman Haefeli wrote:
> >i did a similar test with OSC bundles. it turned out, that you cannot
> >rely on the packet becoming one single list on the receiver side. if it
> >was splitted into two or more tcp packets during tcp transport, the OSC
> >bundle becomes broken.
> >
> >now i am rather more convinced, that any solution based on tcp packets
> >instead of a tcp stream is not going to work.
> >
> I still don't know what you are trying to do so I can't say.
> If you are sending huge amounts of data constantly you really shouldn't be 
> using OSC at all.

all i need is a _robust_ OSC over TCP implementation. the bandwidth used
is not high in average, but i cannot make any assumptions about peaks,
it could well be that 2000 packets are sent at the same time.
the idea is to port netpd to OSC. i don't think, that it is generally a
bad idea. however, it will only work, if it can use the benefits of tcp,
which is: make sure, that all data arrives intact and in the right
order. netpd would break (not in all circumstances, but in many) if some
packets would be dropped. 
currently i don't see, how i can make a robust OSC/TCP connection with

> You could make your own protocol that sends the length of the packet as the 
> first three or four or even more bytes and then use the list objects to chop 
> the stream into pieces. But Pd is really inefficient for this because it's 
> going to convert every single one of your billion bytes into a symbol and 
> put it in memory somewhere.

of course, i could make my own protocol, but the goal to use OSC _is_ to
use OSC.

i asked #networking and they all agreed, that it is up to the
application layer to define packet length (if necessary at all). the
application shouldn't rely in _any_ case on tcp packeting. but this is
what [unpackOSC] currently does. the only fix i can see is making
[unpackOSC] stream based.


Der frühe Vogel fängt den Wurm. Hier gelangen Sie zum neuen Yahoo! Mail: http://mail.yahoo.de

More information about the Pd-list mailing list