Path: utzoo!censor!geac!torsqnt!news-server.csri.toronto.edu!cs.utexas.edu!uunet!fciva!dag
From: dag@fciva.FRANKLIN.COM (Daniel A. Graifer)
Newsgroups: comp.unix.sysv386
Subject: Re: How to get past end of cpio archive on tape
Keywords: eof
Message-ID: <568@fciva.FRANKLIN.COM>
Date: 3 Jan 91 13:01:04 GMT
References: <1990Dec12.050414.15575@bjm.wimsey.bc.ca> <1162@bcs800.UUCP> <301@bria.AIX> <1023@mwtech.UUCP>
Reply-To: dag@fciva.UUCP (Daniel A. Graifer)
Organization: Coastal Capital Funding Corp., McLean, Va.
Lines: 25

In article <1023@mwtech.UUCP> martin@mwtech.UUCP (Martin Weitzel) writes:
%In article <301@bria.AIX> mike@bria.AIX (Mike Stefanik/78125) writes:
%:First you have to skip over the first "part" of the tape that you cpio'd to;
%:use the no-rewind tape device (ours is rmt4) and do:
%:
%:	$ dd if=/dev/rmt4 of=/dev/null bs=512k
%:
%:Then use dd to pull in the last "part" of the tape which is your tar'd files:
%:
%:	$ dd if=/dev/rmt4 of=/tmp/damaged bs=512k
%...
%ALL THIS IS TECHNICALLY CORRECT BUT BOUND TO FAIL FOR TYPICAL CARTRIDGE
%TAPE STREAMERS, SINCE THESE DEVICES PHYSICALLY ERASE ALL OF THE TAPE
%WHEN WRITING THE FIRST TRACK!
%
%(IMHO the topic should go into the FAQ.)
%-- 
%Martin Weitzel, email: martin@mwtech.UUCP, voice: 49-(0)6151-6 56 83

I'm not sure I follow this...How can a drive "Physically Erase" a portion
of tape that has not passed under the head?  I've actually performed the 
above operation on a QIC-24 cartridge.

Dan
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