why number 9 in kill -9 command in unix?
- by Alby
I understand it's off topic, I couldn't find anywhere online and I was thinking maybe programming gurus in the community might know this.
I usually use
kill -9 pid
to kill the job. I always wondered the origin of 9. I looked it up online, and it says
"9 Means KILL signal that is not catchable or ignorable. In other words it would signal process (some running application) to quit immediately" (source: http://wiki.answers.com/Q/What_does_kill_-9_do_in_unix_in_its_entirety)
But, why 9? and what about the other numbers? is there any historical significance or because of the architecture of Unix?
Thanks!