sending TCP message via command line on macosx

sockets command-line tcp spring-xd
user152468 picture user152468 · Mar 30, 2015 · Viewed 7.9k times · Source

For testing purposes I am sending tcp messages to a local server as follows:

echo -e "some message" | netcat localhost 1234

With netcat installed using brew install netcat.

This works fine except for that this blocks for quite a long time (about a minute). I tried to use the options "-w 1" for specifying the timeout, but this does not change anything.

The process listening on the other end is a spring-xd tcp source.

Is there any other way of sending a tcp message that does not block as long?

Answer

Gary Russell picture Gary Russell · Mar 30, 2015

I've not seen such a delay on linux; haven't tried on OS X (it comes with nc instead).

What is your stream definition? The default tcp source expects data to be terminated with CRLF - e.g telnet localhost 1234. You need a RAW decoder for netcat.

EDIT:

I just tested

xd:>stream create foo --definition "tcp --decoder=RAW | log" --deploy

with

$ echo "foo" | nc localhost 1234

and had no problems.

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