Tape retensioning

[John G. De Armond]

In article <1990Jan8.034014.3445 at esegue.segue.boston.ma.us> johnl at esegue.segue.boston.ma.us (John R. Levine) writes:
>In article <1990Jan6.063506.8670 at actrix.co.nz> paul at actrix.co.nz (Paul Gillingwater) writes:
>>But what happens to new users who haven't got a C compiler?
>>How do *they* retension their tapes?  And yes, I tried RTFM...
>
>A quick look at the permuted index in the FM reveals the existence of the 
>"tapecntl" command, and its -t for retension option.
>
>Better luck with the FM next time.

Yes, the FM does mention tapecntl but the existance of this utility and
the /dev/rmt/... devices apparently depend on the tape driver in use.
If a SCSI-based tape is used and accessed through the hpdd driver, then
I assume in this case that the driver is AT&T's and/or part of the hpdd driver. 

If, on the other hand, one is using a Wantek drive and the wt 
device driver supplied by interactive (as am I), then a whole 'nuther set 
of constraints exist.  One should look in wt(7) instead of 
tape(7).  When this driver is used, one has 2 devices to work 
with - /dev/tape which rewinds and /dev/ntape which does not.  
2 ioctl(2) calls are supported - ERASE and RETTENS - both
with obvious meanings.  NO utility is mentioned or exists to my knowledge.
I did the same thing Paul did and wrote a small utility to make the ioctl(2)
calls.  Otherwise, one is SOL.  Sure wish Interactive would support the
Wantek drive as well as it does the SCSI-based drives.

John


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John De Armond, WD4OQC                     | The Fano Factor - 
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