Question

How do I execute the kill -9 in this perl one liner? I have gotten down to where I have the pids listed and can print it out to a file, like so:

ps -ef | grep -v grep |grep /back/mysql | perl -lane '{print "kill -9 $F[1]"}'

Answer 1

OK, heavily edited from my original answer.

First, the straightforward answer:

ps -ef | grep -v grep |grep /back/mysql | perl -lane 'kill 9, $F[1]'

Done.

But grep | grep | perl is kind of a silly way to do that. My initial reaction is “Why do you need Perl?” I would normally do it with awk | kill, saving Perl for more complicated problems that justify the extra typing:

ps -ef | awk '/\/back\/mysql/ {print $2}' | xargs kill -9

(Note that the awk won’t find itself because the string “\/back\/mysql” doesn’t match the pattern /\/back\/mysql/)

You can of course use Perl in place of awk:

ps -ef | perl -lane 'print $F[1] if /\/back\/mysql/' | xargs kill -9

(I deliberately used leaning toothpicks instead of a different delimiter so the process wouldn’t find itself, as in the awk case.)

The question then switches from “Why do you need perl?” to “Why do you need grep/awk/kill?”:

ps -ef | perl -lane 'kill 9, $F[1] if /\/back\/mysql/'