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From: name@portiaStanford.EDU (tony cooper)
Newsgroups: comp.periphs
Subject: What does mt bsf do?
Message-ID: <1990May30.052730.20434@portia.Stanford.EDU>
Date: 30 May 90 05:27:30 GMT
Sender: news@portia.Stanford.EDU (USENET News System)
Reply-To: name@portiaStanford.EDU (tony cooper)
Organization: Stanford University - AIR
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The man page says that mt bsf backspaces one file. Or does it backspace one
filemark (so that in order to backspace one file you have to do mt bsf 2
followed by mt fsf 1). 

How do tape drives that cannot backspace manage to write two filemarks at
the end of the tape when using the norewind device? Drives that can
backspace do it by writing two filemarks at the end of each file and
positioning between the two so that if the tape is rewound there will
be two or if another file is written the second will be written over. I
don't see how drives that cannot backspace can do it. The drive can only
write one after a file is closed. When does it get to write the second?
When the drive is taken off line or is rewound? But what say the tape is
removed without doing either of these?

Is the ANSI standard for 1/2 inch tapes available on line somewhere?

Thanks,
Tony Cooper
tony@popserver.stanford.edu