Here's a big secret about ps and grep: they don't work very well!!! Instead, use ps to do all the work.
Here are some better solutions:
ps -ef | grep username | grep -v grep | awk {'print $2'} | xargs kill
is much more accurate when written:
ps -f -u username | awk '{print $1}' | xargs kill
The first script could be VERY dangerous because grep doesn't care what it matches. If the username is ash, then the first form kills all copies of bash (every user) as well as the unhasdaemon (not good!) and so on. The second form only returns processes used by a specific (and exact match) username.
And the other example will kill every process owned by mozilla9 as well as the mozilla process. Rather than:
kill -9 $(ps -aex | grep mozilla | grep -v grep | awk '{print $1}')
Use this:
kill $(UNIX95= ps -C mozilla -o pid | grep -v PID)
In this case, grep gets rid of the column title line PID and leaves zero or more process ID numbers. ps looks at the exact process name, so -C sh will not match bash or ksh.
Bill Hassell, sysadmin
