No no no. Don't use kill -9.<p>It doesn't give the process a chance to cleanly:<p>1) shut down socket connections<p>2) clean up temp files<p>3) inform its children that it is going away<p>4) reset its terminal characteristics<p>and so on and so on and so on.<p>Generally, send 15, and wait a second or two, and if that doesn't work, send 2, and if that doesn't work, send 1. If that doesn't, REMOVE THE BINARY because the program is badly behaved!<p>Don't use kill -9. Don't bring out the combine harvester just to tidy up the flower pot.<p>Credit: Randal L. Schwartz<p>Source: http://partmaps.org/era/unix/award.html#uuk9letter
As mentioned, SIGTERM can be caught and gives the process a chance to clean up. SIGKILL, the nuclear option, cannot be blocked.<p>Related: Solaris tip for Linux admins: <i>killall</i> does exactly what it says and not what you think.