Path: utzoo!attcan!uunet!lll-winken!lll-tis!ames!xanth!nic.MR.NET!rhesus!larry!jwp
From: jwp@larry.UUCP (Jeffrey W Percival)
Newsgroups: comp.unix.wizards
Subject: Ultrix tape job is unkillable!
Keywords: ultrix tapes
Message-ID: <476@larry.UUCP>
Date: 15 Dec 88 00:30:36 GMT
Organization: UW-Madison Space Astronomy Lab
Lines: 18

I am running ULTRIX 2.something and wrote a C program to
read records off a 6250 BPI tape and write them on stdout.
I use read(2) to read the tape records, and pipe the output
to some other program.  Like this:

	readtape -f /dev/rmt1h | dowork > results

So, this thing is grinding along and I decide to trash the job,
so instead of interrupting the process with cntl/C, I pop the
drive off-line (thinking the jobs will abort).  Later, I find
the "readtape" job hanging around with a priority of -5, and
I couldn't kill it.  I tried putting a tape back on line to
see if it was waiting for something, I sent kill signals (IO, HUP, 9)
to it to no avail.  A reboot finally cleared things up.

Now (besides the obvious, cntl/C to the program), what do I
do in the future when we have such a hung process?
-- 
Jeff Percival (jwp@larry.sal.wisc.edu)