Unix/Linux: Finding and Killing Processes by User

If you’ve ever run ps aux | grep user to list processes and hunt for process IDs, you’ll be happy to know there is a simpler alternative. Both finding and killing processes owned by a particular user is made simple using the handy pgrep and pkill utilities.

Listing Processes with pgrep

Listing all the processes owned by the user raam can be done like this (the -l switch causes the output to include the process name):

$ pgrep -l -u raam
9614 screen
9628 bash
9644 irssi
16165 bash
16297 rtorrent
19462 ssh
19515 bash
19526 ssh
20964 sshd

You can also filter the list of results by appending a full (or partial) process name to the command:

$ pgrep -l -u raam bash
9628 bash
16165 bash
19515 bash

Killing Processes with pkill

The pkill command does basically the same thing as pgrep, except it kills the processes instead of listing them. This is useful if you have a user with several dead processes, or if you were deleting a user and you wanted to kill any running processes first.

Killing all the processes owned by the user raam looks like this:

$ pkill -u raam

And once again, if you only wanted to kill all the bash processes owned by raam, you would append the process name to the command:

$ pkill -u raam bash

As always, check the man pages for pgrep and pkill for more information and switch options.