Shell Programming and Scripting

Hello all... new to these forums and a bit of a newbie with linux aswell.

I need to figure out how to write a shell script to kill a process by name as given to the script as an argument. I've got that part working OK, but i need to make sure that the script does not allow processes that are owned by root to be killed.

I have tried all combinations of IF statements, but i can't seem to get any to work

Any help would be appreciated, Thanks.

Simple idea

Code:

pid=`ps aux|grep $1|grep -v root|awk '{print $2}'`
kill -9 $pid

Code:

process_id=`ps aux | grep $1 | grep -v root | grep -v grep | awk '{print $2}'`
 
if [ $? -eq "0" ]; then
kill -9 $process_id
fi

if you get more than one output for the below command

Code:

ps aux | grep $1 | grep -v root | grep -v grep | awk '{print $2}'

then, use the below one

Code:

process_id=`ps aux | grep $1 | grep -v root | grep -v grep | awk '{print $2}'` 
if [ $? -eq "0" ]; then
for i in $process_id;do kill -9 $i;done
fi

None of the solutions provided are very good (no offense intended to their respective providers). They all check for the presence of the command name and "root" in ps output, but do not constrain their presence to their respective fields. They will fail if the command name contains "root" or "grep" (so you can't use it to kill grep, egrep, fgrep, etc). Also, when identifying priviliged processes, it's best to check for id 0 instead of the name 'root', unless you are specifically interested in "root" and not privilege in general.

If your system has pkill, with the appropriate options, it is all you need.

Regards,
Alister

Thanks for the responses. I have tried the examples posted but none of them seem to work. They either produce errors or kill the process regardless of the owner.

I have done a bit of reading and pkill does seem to be the easiest option. Could anyone suggest how to implement it into my example?

Thanks again.

Ps. I am using Debian if that makes a difference.

If you stated what errors it might help fix the programs.

I eventually wrote something that works... it's a little buggy but it does the job.

Code:

#!/bin/bash
process=`pgrep -U root "$1" | wc -l`
if [ $process -ge 1 ]; then
echo It is not safe to kill this process...
else
pkill $1
echo $1 process killed...
fi

Thanks for the help.