<defunct> processes (was Re: Trouble killing processes in SysV/AT)

[Jonathan Payne]

<defunct> processes are processes that have terminated but haven't yet
been wait(2)'d for.  All process must be waited for by somebody, usually
the parent, before they go completely away.  If you think about it, that
makes sense, because you hardly ever just want a process that finishes to
go away without being able to tell how it exited (via wait(2)).

If the parent dies before waiting for any of it's children, it becomes
the responsibility of the parent of the parent to do the waiting, which
is usually init(8).  Init is smart enough to notice when a process it
just waited for is one which means that a person logged out, so it can
fire up another login, etc.

Anyway, I wonder how many other people have answered this message ...