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flxkrmr
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I try to develope a small android application to control ardour via OSC messages. Doing that, I stumbled across some OSC reply messages send by Ardour. Theses messages start with "#reply". Is there a specification for this reply format somewhere?
These messages came as an response to the "/strip_list" message from my application.

Thanks :)

paul
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Did you read the manual?

flxkrmr
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You mean this: http://manual.ardour.org/using-control-surfaces/controlling-ardour-with-osc/feedback-in-osc/ ?
Yes a few times, but as I mentioned the messages come in with a trailing "#reply" and no OSC like address pattern, which looks very similar to the OSC "#bundle" messages.
I thought it might be something defined in a new OSC spec, or something Ardour specific, but couldn't find any information about it. Am I missing something?

lenovens
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#reply is handled at the receiving end pretty much the same as /command message. Remember that all OSC content is sent as text. #reply is not uncommon in OSC for a reply to a query. However, Ardour can also send non-reply messages when a controllable changes value but in this case the feedback matches the original command. Liblo for example will show #reply as the "path". It is just a path that starts with # instead of /.

flxkrmr
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Ok thanks!

fischerman
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Is this compliant with the OSC spec? It is neither a valid OSC message (which must start with a '/') nor an OSC bundle.
I try to implement a server using Golang.

lenovens
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While the query code is quite old, http://opensoundcontrol.org/files/osc-query-system.pdf does indicate that #reply is a valid addition to OSC meant for OSC 1.1. So while not a part of OSC 1.0, it seems to be a well known and used part of the yet unpublished OSC 1.1. OSC 1.1 ... where is it? Why was it not officially released? Because the spec was being maintained as part of a "class project" at http://cnmat.berkeley.edu/. The funding for them to host/maintain the spec has gone away and nobody has stepped forward to maintain or improve OSC. There have been papers about various things since OSC 1.0, but no one has set up a committee to finalize anything. So we have what we have and most everything is "do what you like".

All of the new code since Ardour 5.0 has done feedback in the same form as the commands. That is, /strip/gain as a command should expect /strip/gain as feedback too. All of the query/#reply code is older. With the exception of the plugin query added recently by someone who was already using the old query code. Most libraries should allow an OSC command to be any arbitrary text string which the application can do with as it likes. Ardour uses liblo.