How to determine status of upstart job in bash script?

Question

How do you determine if an upstart job is running inside of a Bash script? That is I need a "boolean" value to do something like:

#!/bin/bash
if [ determine_if_job_x_is_running ]; then
  echo "I see upstart job X is running, please stop it before ..."
fi

Answer 1

Create your own Bash function and put this in your ~/.bashrc:

check_upstart_service(){
    status $1 | grep -q "^$1 start" > /dev/null
    return $?
}

I really dislike the way of parsing output, but I don't see another obvious way. And in this case the output of <service name> start is very reliable as it's specified in the Upstart documentation.

Now you can use it like this:

if check_upstart_service ssh; then echo "running"; else echo "stopped"; fi

Answer 2

You would use DBUS to query the status of that particular service.

$ job=myjob
$ dbus-send --system --print-reply --dest=com.ubuntu.Upstart /com/ubuntu/Upstart/jobs/${job}/_ org.freedesktop.DBus.Properties.GetAll string:''

http://upstart.ubuntu.com/cookbook/#get-status-of-job-via-d-bus

Note that if you're writing your own upstart job, you should use upstart events or package dependencies instead.

Answer 3

Normally you use a PID file but you can also use pgrep to check your processes. Assume your service is called jobX this will work:

if [ $(pgrep jobX) ]; then

Or even better

if pgrep jobX > /dev/null 2>&1