what is the process number of a "running application" ?

[poma]

On 14.01.2015 18:32, Angelo Moreschini wrote:
> thank you,
> 
> I found a very simple as well very elegant way to kill an application, if
> it has a graphic interface on the screen:
> http://community.linuxmint.com/tutorial/view/50
> ---
> 
> From the command line you can type: "sudo xkill"
> the result of this command is a a "particular shape of the cursor" that can
> be used to terminate a program, simply clicking on his window with this
> cursor.. [?].
> 
> It works really very good..
> 

man 1 xkill
...
CAVEATS
This command does not provide any warranty that the application whose connection to the X server is closed will abort nicely,
or even abort at all. All this command does is to close the connection to the X server.
Many existing applications do indeed abort when their connection to the X server is closed, but some can choose to continue.