On Sat, 8 Nov 1997 07:22:27 -0800 (PST) 
 "Gerald C. Simmons" <simmons@darykon.cet.com> wrote:

 > This, however, does not:
 > simmons@dakkon[57]% tar cvzf /dev/rst0 edge
 > edge/
 > edge/OTE.cardlist
 > edge/OnTheEdge.cardlist
 > tar (child): can't write to /dev/rst0 : Input/output error
 > simmons@dakkon[58]%
 > 
 > Nov  8 07:14:53 dakkon /netbsd: st0: bad request, must be multiple of 512
 > 
 > The question is: Is "z" not a valid option for tapes? Or is there something
 > missing in the driver. (I saw something in ther about residuals not being
 > finished or something. Is this related?)

Tapes need to be written in "blocks".  tar(1) does this by default, but
the -z option effectively pipes the output of tar through gzip(1), which
does NOT write in "blocks".

You can do what you want by doing:

	tar cvzf - edge | dd of=/dev/rst0 obs=512

Jason R. Thorpe                                       thorpej@nas.nasa.gov
NASA Ames Research Center                            Home: +1 408 866 1912
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