How do I kill a backgrounded/detached ssh session?

Question

I am using the program synergy together with an ssh tunnel

It works, i just have to open an console an type these two commands:

ssh -f -N -L localhos         


        

Answer 1

Based on the very good answer of @ghoti, here is a simpler script (for testing) utilising the SSH control sockets without the need of extra configuration:

#!/bin/bash
if ssh -fN -MS /tmp/mysocket -L localhost:12345:otherHost:12345 otherUser@otherHost; then
    synergyc localhost
    ssh -S /tmp/mysocket -O exit otherHost
fi

synergyc will be only started if tunnel has been established successfully, which itself will be closed as soon as synergyc returns. Albeit the solution lacks proper error reporting.