I am trying to use a software-defined radio receiver to get data from a wireless thermometer. The program that controls the radio sends a stream of JSON strings separated by newline characters to its standard output. (All of this is running on a Pi with Raspbian.) If I start the program with the exe…

The solution may be a function node that buffers and concatenates payloads till it sees a CR then sends the message on.

Another head slap. Would the split node do this for you ? (Not near computer to check) Maybe not but would make a good PR to add it. :man_facepalming:

[image] dceejay: Would the split node do this for you ? Possibly, though at first glance I doubt it, because the payload I want is already split between two or more messages. I'll check. And thanks for the emoji -- I know it will come in handy.

@Colin 's suggestion solves my immediate problem. I expect to play a bit more with sdr, so if I find a need to wrap rtl_sdr in a contributed node or modify the rtl_power node, I will start a new thread. Thanks again for all the help.

I'm having a similar issue with ffmpeg in an exec node only sending partial frames when converting rtsp streams into jpeg imags. Looking for CR or any specific character won't work for binary data buffers.

Do you mean you receive the data as multiple partial frames? So it is all there but split up?

[image] dceejay: Would the split node do this for you? I was much too quick to dismiss this suggestion. It worked brilliantly, once I realized (as I'm sure @dceejay intended) that the "Handle as a stream of messages" option should be enabled. For the record, and for the benefit of anyone (li…

I'm a lot fuzzy about how to do this. Do I put the split on the output of my exec node and then feed them into a join node to get the full jpeg image? Mine are binary buffers not strings.

Hey @wb666greene , If you have some spare time, it would be nice if you could share a 'simple' flow that we can use to reproduce the problem. Was just wondering: suppose you execute a 'curl' command from an exec-node, to load a very large image from the web. If that image also arrives on the outpu…

I think it (high watermark) is about 16k on windows and 64k on linux.

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Exec and daemon nodes break up a data stream

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wb666greene 25 May 2019 19:50 20

I'm trying to figure out is this is the case.

Tcp in node loosing/stacking messages

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Exec and daemon nodes break up a data stream

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