You need to use xkill command. It kills a client by its X resource and not by process ID. For example, your application may not be responding kill request. Even if you try to kill you see application window.
xkill is a utility for forcing the X server to close connections to clients. This program is very dangerous, but is useful for aborting programs that have displayed undesired windows on a user's screen.
Open a terminal type the following command:
$ xkill
By default xkill will display a special cursor with which you should select a window to be kill. Click on the application which you want to abort forcefully or select the X window / application whose client you wish to kill with button 1. If a pointer button is pressed over a non-root window, the server will close its connection to the client that created the window.
How do I kill the application using the X identifier?
An easy way to find out the id of a window, is running a command like:
$ xwininfo
You need to select target window with the mouse to get information about windows. Here, is a sample output from my gnome-terminal window:
xwininfo: Please select the window about which you
would like information by clicking the
mouse in that window.
xwininfo: Window id: 0x6e4c0a7 "vivek@wks01: ~"
Absolute upper-left X: 2443
Absolute upper-left Y: 231
Relative upper-left X: 2443
Relative upper-left Y: 231
Width: 983
Height: 636
Depth: 32
Visual: 0x104
Visual Class: TrueColor
Border width: 0
Class: InputOutput
Colormap: 0x6e00003 (not installed)
Bit Gravity State: NorthWestGravity
Window Gravity State: NorthWestGravity
Backing Store State: NotUseful
Save Under State: no
Map State: IsViewable
Override Redirect State: no
Corners: +2443+231 -414+231 -414-333 +2443-333
-geometry 80x24+2443+231
Note down the window id # 0x6e4c0a7. You can also use the following syntax:
xwininfo | awk '/Window id:/ {print $4}'
Sample outputs:
0x6e4c0a7
Finally, run xkill command as follows:
xkill -id 0x6e4c0a7
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{ 2 comments… read them below or add one }
this command is cool!!!
best command ever :)