I'm trying to receive data from a sensor that is connected to my wifi network. I can see the data streaming into a browser window, as a string of numbers, coming in from a specific IP address and port number. But when I bang [listen 8080( into [netrecieve] and [print] the result I get: bind: Address already in use (98).

Is there a way to just scrape that port into Pd somehow?

cheers!

@glitchpop Hello...... for multiple "listeners" you need to use udp, and not tcp...... [netreceive -u 8080].... but your sensor will need to be sending udp (tcp and udp can share the same port number, but are different protocols..... they are different namespaces).

Tcp binds to the port, as it checks for missing packets and requests a resend, and checks that the data is arriving in the correct order.......... so only one "listener" is possible.
Udp just "listens", does no checksum, and cannot know if the data is corrupt, so cannot request a resend....... it treats the socket as a "broadcast" address, and so can have multiple receivers.

If you have to use tcp you will have to connect [netreceive] first....... and then your browser will be "in a bind"...... or rather "not".......
David.

Hi whale-av, thanks for your reply. I managed to get this up another way a couple of months back, but now I'm back making an updated version. I ended up using pd-extended last time and so found that [tcpreceive] work well. However now I am using Raspian Jessie and Pd Vanilla 0.46.2 I cannot use that object any more.

What you said makes sense I am now attempting to use a [netreceive 8010 0] and then using curl to route my data to the same port (8010). This worked with [tcpreceive] in Extended but I couldn't get it to work with [netreceive]. It still isn't working with [netreceive] now.

I know I have some work to do to separate out the data stream once it's coming through but at this stage even connecting [print] to [netreceive] yields no data. Curl (in my terminal) is acting like it's running and connected, for example if I run the curl scrip without running the Pd patch and building the [netrecieve] first the curl doesn't connect (as you explained before).

Do I need to be doing something to somehow "wake up" [netreceive] to receive the data? If so I can't find it in the documentation. Any suggestions would be very much appreciated.

@glitchpop It should just listen and receive without outside help.
[netreceive] should broadcast it's port (so that it can be connected to) as it is created. If the sender is showing "connected" then presumably it was found. Are you certain that data is being sent?

Try this on the rpi....... just to check that [netreceive] is working at all.....net.pd
David

Thanks David, yes that works. It works with [netsend] but it's not connecting to my curl script. Except it seems to be half connecting because the curl script only runs when there's a [netreceive] in Pd (with the correct matching port number) or instead if I open a web browser to the same IP address it completely works.

As I said [tcpreceive] worked fine but [netreceive] somehow doesn't.

@glitchpop If you give it the -b flag does anything print? Otherwise I must think that nothing is being sent.....
Do you have a means to packet sniff? Or a program that will show ports, connections, and quantities of data sent.
https://snippets.khromov.se/show-open-ports-and-what-program-is-using-them/
http://www.binarytides.com/linux-netstat-command-examples/
David.

Ok this is pretty weird. wasn't working with -b flag before but now it is. Which is great thank you! However it still doesn't work without the -b flag. Which means I'm going to have re-encode from binary back to numbers and symbols (the data is separated by commas). David, do you know of any currently supported objects to do this?

I was using [moocow/bytes2any] before but I think that lib is now also defunct. Not having much luck at the moment.

@glitchpop There is a remote way-out chance that if the moocow .dll was compiled with "mono" then just copying it into Pd from windows would work. What system were you using for extended? The object might have a .so file (bytes2any.so), or that file name with some other library name extension? Otherwise you can try to import the whole moocow library? Sorry, I have little experience with Pd on Linux, and even less with vanilla.

I'm all linux. The previous build was with Raspian Wheezy, now on RAspian Jessie. Thanks for all your help David. I'll muddle through it.

@glitchpop Hmm.... I dumped Jessie. I have a load of rpi2 B's doing boring headless tasks, and after a couple of days trying to make them do what they did easily under Wheezy I gave up......
David.