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

[John Owens]

In article <77 at lakart.UUCP>, dg at lakart.UUCP (David Goodenough) writes:
> did lots and lots of popen("command", "w") calls. I fired it up background,
 . . . 
> there, but so were about 40 processes marked STAT == Z, COMMAND == <defunct>.
 . . .
> TT == 0 (/dev/tty0), but the controlling TT of these defunct processes was
> drifting all over hell's half acre: TT == co, then TT == h1, then TT == dx -
> all for the same process!

This is not the same situation.  These processes have actually been killed -
they have received the "9" signal and have exit-ed.  The difference is that
they have not been "wait"ed for by their parent process, and are considered
"zombies" - only a small portion of their original information is still
present.  Specifically, the controlling tty is no longer present, so
ps will show random values there.

Mr. Paul's processes were not zombie processes - they were still "alive",
just hung in a kernel sleep(), as has been so well explained.

-- 
John Owens		SMART HOUSE Development Venture
john at jetson.UUCP	(old uucp) uunet!jetson!john
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