Home / ubuntu / Questions / 215814
Accepted
Hanynowsky
Asked: 2012-11-12 08:51:55 +0800 CST

How to xkill an application by its id?

  • 772

I need to simulate the behavior of the keyboard shortcut (ALT+F4) using Terminal for a given application.

If I open for example gedit and click ALT + F4 , then GEDIT will be xkilled. If I want to achieve same thing using Terminal, how should I proceed?

The following command (in order to kill gedit process) works fine:

kill $eval `pidof gedit`

yet, the command

xkill -id gedit

prompts me to click on the application client window in order to xkill it, thing That I want to avoid from the beginning.

The reason why I want to achieve this behavior is that some applications clients keep their process running, even though you ALT+F4 it. My need is that I have an application that starts up on every login and I need to automatically close its client 3 or 5 seconds after it shows up.

xorg

4 Answers

  1. Best Answer

    An equivalent of xkill is the windowkill function in xdotool. If you don't have xdotool installed, please run 

    sudo apt-get install xdotool

    With this tool you can indeed kill a window by using the search option and by specifying its class:

    xdotool search --class gedit windowkill

    You can find the pid of the process with getwindowpid, but just specifying the name of the class of window (i.e --class gedit) is enough. The tool is non-interactive in the sense that you do not need to click on a window to kill it as you sometimes need to do with xkill.

    More information on the options available with xdotool are available with man xdotool and at the Ubuntu manpages online. The manpages explain well how xdotool can be incorporated into a script much easier than xkill could be.

    So I think probably xdotool's windowkill option is what you want and it may be more handy than that of xkill.

    However, if you still want to use xkill and feed it the window's resource id, so that it closes the window without prompting you, you could parse the output of xwininfo, as in this example using the program Meld:

    xkill -id $(xwininfo -name Meld | awk -F ':*"*' '{print $3}')

    However, the name of the program sent to xwininfo must be in the proper case, so launch the program beforehand, and, in our example here, see if it is Meld or meld.

    I prefer the xdotool command I gave above, as the case doesn't have to be correct: Meld or meld will work as the search --name switch instead uses regex to match a given string and ignores the case.

    • 2

  2. you can use killall which will send a TERMSIG (terminate signal) to the application you specify. you can use killall with the following command 

    killall <id>

    for example, you can close firefox with 

    kilall firefox

    if for some reason you must find the correct id of an application/process, you can always use ps to see all running processes and their names.

    • 1 
  3. kill -9 <id>

    will definitely kill everything associated with that pid.

    to find the pid, I use

    ps -u $USER -f | grep gedit

    they can then be incorporated into one command if you need to do it often

    • 1

  4. Use top Command to get particular process Id. Note down it and type following command to kill Process.

    kill <process id>
    • 0