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Path: euryale.cc.adfa.oz.au!newshost.carno.net.au!harbinger.cc.monash.edu.au!munnari.OZ.AU!news.ecn.uoknor.edu!feed1.news.erols.com!worldnet.att.net!newsfeed.nacamar.de!news.apfel.de!fu-berlin.de!irz401!orion.sax.de!uriah.heep!news From: j@uriah.heep.sax.de (J Wunsch) Newsgroups: comp.unix.bsd.freebsd.misc Subject: Re: Tar not writing Multivolumes Date: 5 Apr 1997 15:04:22 GMT Organization: Private BSD site, Dresden Lines: 47 Message-ID: <5i5plm$8jd@uriah.heep.sax.de> References: <5i2fc9$2u9$1@otis.netspace.net.au> Reply-To: joerg_wunsch@uriah.heep.sax.de (Joerg Wunsch) NNTP-Posting-Host: localhost.heep.sax.de Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Newsreader: knews 0.9.6 X-Phone: +49-351-2012 669 X-PGP-Fingerprint: DC 47 E6 E4 FF A6 E9 8F 93 21 E0 7D F9 12 D6 4E Xref: euryale.cc.adfa.oz.au comp.unix.bsd.freebsd.misc:38549 mheath@netspace.net.au (Mark Heath) wrote: > > i've tried to create a multi volume archive on disk using the following > tar command > > tar cMf /dev/fd0 filetoarchive First, you're making a very common but unfortunate mistake: you're abusing the buffered device (/dev/fd0) for things where you should use the raw device (/dev/rfd0). There are basically three reasons for not using buffered devices for raw data: . you have no guarantee when the data will actually be written, since the writes are buffered, . you're blasting your filesystem buffer cache for no good reason, and . writes on the buffered device succeed prematurely, so if an error will be detected by the driver later on, the application has already got a `good' status indication. #3 is probably also what makes it impossible to write multi-volume tar archives to a buffered device (i'm not sure, i've never tried this). Second, you haven't indicated which version of FreeBSD you're using. The EOF handling in the floppy disk driver used to be broken for years. I've fixed it by: revision 1.93 date: 1996/11/02 23:31:11; author: joerg; state: Exp; lines: +36 -28 Fix the broken EOF handling in the floppy driver. The most obvious appearance of this bug was the malfunctioning -M option in GNU tar (it worked only by explicitly specifying -L). Reviewed by: bde, and partially corrected according to his comments Driver versions prior to this date always required the -L1440 option to tar in order to read and write multi-volume archives correctly. -- cheers, J"org joerg_wunsch@uriah.heep.sax.de -- http://www.sax.de/~joerg/ -- NIC: JW11-RIPE Never trust an operating system you don't have sources for. ;-)