Return to BSD News archive
Newsgroups: comp.unix.bsd.freebsd.misc
Path: euryale.cc.adfa.oz.au!newshost.anu.edu.au!harbinger.cc.monash.edu.au!news.rmit.EDU.AU!news.unimelb.EDU.AU!munnari.OZ.AU!spool.mu.edu!howland.reston.ans.net!Germany.EU.net!Dortmund.Germany.EU.net!nntp.gmd.de!news.rwth-aachen.de!newsserver.rrzn.uni-hannover.de!hrz-ws11.hrz.uni-kassel.de!phase23.dinoex.sub.org!citylink.dinoex.sub.org!peter
From: peter@citylink.dinoex.sub.org (Peter Much)
Subject: Re: tpqic02...
Content-Type: text/plain; charset=ISO-8859-1
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Organization: Buero fuer Sektenforschung und Qualitaetspruefung in der Esoterik
Message-ID: <DJzs44.Ets@citylink.dinoex.sub.org>
References: <4a6vve$l46@senator-bedfellow.mit.edu> <4anj90$mqa@uriah.heep.sax.de> <DJo68z.7qH@citylink.dinoex.sub.org> <4b79de$52i@uriah.heep.sax.de>
Date: Fri, 22 Dec 1995 14:26:27 GMT
Lines: 58
In article <4b79de$52i@uriah.heep.sax.de>,
J Wunsch <joerg_wunsch@uriah.heep.sax.de> wrote:
>peter@citylink.dinoex.sub.org (Peter Much) writes:
>> 1. The "mt fsf" command returns immediately, while the tape is winding.
>
>This seems to be intention, though it differs from the behaviour of
>the `st' driver.
Hello Joerg!
Interim, I have been told, that immediate-return behaviour being usual
on most unixes. Seems to remain from times ago when terminals were few?
>> 2. The "dd" command reports an error after waiting 60 secs. on the
>> winding, i.e. blocked, device.
>
>Hmm, there must be a bug somewhere. The following lines of code from
>wtopen() are supposed to wait until the rewind is complete:
Interim, I followed the going-on with a C-program. Following happened:
The open() succeeds, the read() waits 'til rewind finishes, and then comes
back with EIO error. A following call to read() will succeed and work
as expected.(*) (The 60 secs. came from all tape-files having similar
lengths.)
And I'm very sure there *is* a bug somewhere: After some stangeness occured,
I put back my kernel changes to original state, and worked around the EIO
error with a user-level C-programm (as a substitute for "dd"), that would
simply retry the read(). This did crash the whole system on extensive tape
read operations (while lots of other programs running); e.g. the news-system
would report errors like "catt: not found" or
"newsrun: cannot execute togo.[1-9]", the system would hang with the X
session full of mis-coloured pixels, and similar funny things.
Interesting, since the system did run stable (fascinating stable!) for 2
months, before I started using the tape. So I can't believe this being a
hardware problem.
I'm just now updating from 2.1-STABLE to 2.1.0-RELEASE, and severely chek-
king my hardware - hope it disappears then. If it doesn't, I'll send a
detailed report to the "hackers"-list.
Over all, the OS has an incredibly high quality level (after i had under-
stood the new disk-partitoning logic, i was stunned with fascination!),
and i think, we should try to get the minor peripherials to that level, too.
(*) If, as You say, this is not the expected behaviour, then the tape con-
troller might do something unexpected when switching back to ready. It's a
WANGTEK ASSY 30850-008 Rev.J, manufactured late 1989. But even then, this
shouldn't damage the system's memory contents, i think.
Peter
--
stille nacht - heilige nacht - alles saeuft - einer wacht:
City-Link Kassel - rebooting every solstice!
----------------------------------------------------------------------------
Write to: Peter Much * Koelnische Str. 22 * D-34117 Kassel * +49-561-774961
peter@citylink.dinoex.sub.org * much@hrz.uni-kassel.de