I believe this has come up before, but I can't find discussion
in the FAQs, so ...
Someone here has a DAT tape which originally contained a large
number of tar archives. Someone overwrote the beginning of the
tape with three small tar archives. Of course, everything that
got overwritten is gone, as (probably) is whichever tar archive
was partially overwritten. But what about the ones following?
I was hoping that one could do some variant of
mt seod # to get to end of the "new" stuff
mt fsf 1 # to skip the partially-overwritten tar archive
after which one could use "mt fsf N" + "tar x" to extract stuff
from an archive which followed the mistakenly-written ones.
However, I can't find any way to persuade the system to continue
past EOD. The manpage implies that one can use "mt seod" to get
to the current end of media for purposes of appending data. But
attempts to read beyond it fail.
>From one angle, this makes sense. (After all, why would anyone
*want* to read beyond the end of the data on the tape?) But of
course, there are situations where one would want to do exactly
that (such as this one).
Is the refusal to read past EOD done by clever firmware in the
drive itself, or by the SCSI tape driver? If the latter case,
is there any way to reconfigure things to permit a nonstandard
operation of this sort? (I'm even willing to patch the running
kernel after the "mt seod" to fool the driver into believing it
isn't really at EOD.)
Any and all suggestions appreciated. As usual, many TIA.
Mark Bartelt 416/978-5619
Canadian Institute for mark_at_cita.utoronto.ca
Theoretical Astrophysics
http://www.cita.utoronto.ca/~mark
"Nur eine Waffel taugt!" -- Parsifal, in an Eggo commercial
Received on Wed Jan 29 1997 - 20:43:34 NZDT