Kill a process run by a specific user

Question

Let's say that I have several users running ''ruby'' processes simultaneously. How do I write a shell command to kill the ''ruby'' process of one particular user? (I'm on CentOS 5.5.)

Answer 1

pkill is good good for this:

pkill -u particularUser ruby

You can use pgrep with this as a test before you run it to see the process name and pid of what will be signaled:

pgrep -u particularUser -l ruby

Answer 2

You can use the -u switch to killall to limit the scope to a single users. So for user abc you could do: killall -u abc /usr/bin/ruby (or whatever will match the ruby proccesses)

from man killall:

-u, --user
Kill only processes the specified user owns. Command names are optional.

Answer 3

As a worst-case, if you can login or su - as the user, you can issue the famed kill -9 -1 command AS the user to clean up their processes.

Do NOT run as root :)