Originally Posted by paddyjoy
Thanks I'll remember that for next time. It's annoying when a program like rpm or yum gets zombied like this because it locks some files and the only thing I can do is reboot before I can use that program again.
Zombies happen when a parent forks a child process and the child dies. The child becomes a zombie until either (1) the parent executes a wait() command on the child, or (2) the parent dies. The "parent executes a wait()" scenerio is where the somewhat morbid recommendation that "Parents should reap their dead children" comes from. The next time you zombie a process and can't seem to get rid of it, try logging off and back on again. That may kill the parent, thus freeing the zombie without a reboot. I'm not really familiar with the workings of rpm (I use Debain and dpkg/apt-get), but you can see after your first kill attempt at rpm that it looses it's controlling TTY (was "pts/1" before the kill, then "?" after the kill). I always that zombies showed up in a ps listing as "<defunct>". That's the way it's been for years on many different Unix systems I've worked with. Don't know specifically about Linux though. I haven't been using Linux all that long and haven't looked closely.