Yeah, that´s what I hoped to be able to avoid
If someone else has the same problem, I played around alot, and finally my solution is using the telnetlib in python, and a pythonshell node to trigger the script and get the information back.
Code of the python script with my telnet´s server IP address, port 23 and 1 sec timeout is
tn = telnetlib.Telnet("192.168.178.180", 23, 1)
tn.write(sys.argv.encode() + "\r\n")
print ("Unable to connect to Telnet server")
This way I can call the script with the input of the node as the sended telnet command.
Here, a new connection is established every time I send a command, otherwise my AVR would not accept them.
print (tn.read_some()) can be used to print out the response. If you need the f.e. third response , add two
tn.read_some() before it, every reads a line. Careful, it is a blocking process.
the prints are the output of the node then, I have uncommented it on try block to speed up the node ~150ms.
Which leads me to my final question: what is the best way to get the information the node is ready again? Node itself does not have such a functionality, status node always reads "unknown". As it always generates an output ("" or "thePrintedText"), I thought I could use this as a signal. Problem is, I need it to be handled very fast, so setting an value every time I get an output and read it on the entrance within a loop would be a way, but I assume not the best (fastest^^).
Maybe someone knows an "and-node" with a timeout option and two inputs or something, which could directly react on the output?