Well, this one is not so hard after all. You have many ways to do it. You can do it by finding the PID of the program which stopped responding, and then using the kill command to terminate it, or you can use the xkill tool or other graphical tools such as the ones that show the process tree.
The first thing to do to terminate a misbehaving program is to find its PID, or process ID. To do so, execute the following from a console: ps aux | grep mozilla, supposing that Mozilla is the misbehaving program. You will get something like the following:
peter 3505 7.7 23.1 24816 15076 pts/2 Z 21:29 0:02 /usr/lib/mozilla
This tells us, amongst other things, that Mozilla was started
by user peter and that its PID is 3505
.
Now that we have the PID of the misbehaving program, we can execute the kill command to terminate it. So we execute the following: kill -9 3505, and that's it! Mozilla will be killed. Note that this is only to be used when the program doesn't respond to your input anymore. Do not use it as a standard means of exiting from applications.
Actually, what we
have done was send the KILL
signal to the
process number 3505
. The
kill command accepts other signals besides
KILL
, so you can have greater control over your
processes. For more info, see kill(1).