root@netdev.Comsys.COM (Alex Huppenthal) (03/14/90)
Warning - Warning ------ HACK METHOD APPROACHING -------
Discovery note:
SCO XENIX 2.3.2 GT
Adaptec AHA-1540-A SCSI Controller
Archive 2150s Tape drive
[ Disclaimer: I don't personally reccommend this, but it does work here. ]
The Problem:
How can I add to the end of tar archives ? tar cv, tar cv works, but
tape rewind, tape rfm, tar cv - does not!
1. Change the /etc/default/tar file to archive=/dev/nrct0
2. Change the /etc/default/tape file to /dev/nrct0
3. tar cv file1
4. tar cv file2
5. tape rewind
6. tape rfm - moves you to the end of file one
7. tape rfm - moves you to the end of file two
8. tape rfm - this is not a failure, it's a *feature* :-)
it will complain, not able to do rfm on /dev/nrct0,
at this point ( which makes sense )
9. tar cv file3
10. tape rewind
11. tape rfm
12. tape rfm
13. tape rfm - now you are positioned at the end of the second file.
14. tar tvf ( or xvf ) /dev/rct0 ( can you beleive this? I can't )
15. THIS WORKS..... ^^^^--- notice *rct0* not nrct0, - ask SCO why!
I am amazed that we've stumbled on this combination of elements to
force this to work properly. The technique is bloody awful, but the
results to us - are worth it. We now can make use of tape space.
I hope you folks at SCO are watching, given that a way exists now
( albeit crude, and ruthless ), to add to tape archives with this configuration.
Now, don't you think a more graceful, and elegant approach should be available
on YOUR XENIX or UNIX product?
Good luck,
-Alex
--
Alex Internet: root@comsys.COM
Huppenthal UUCP: {cs.utexas.edu!texbell}!netdev!alex
Communication Systems Research 6045 Buffridge Tr, Dallas, TX 75252 steve@wattres.UUCP (Steve Watt) (03/14/90)
In article <262@netdev.Comsys.COM> root@netdev.Comsys.COM (Alex Huppenthal) writes:
< How can I add to the end of tar archives ? tar cv, tar cv works, but
< tape rewind, tape rfm, tar cv - does not!
<
< 1. Change the /etc/default/tar file to archive=/dev/nrct0
< 2. Change the /etc/default/tape file to /dev/nrct0
< 3. tar cv file1
< 4. tar cv file2
< 5. tape rewind
< 6. tape rfm - moves you to the end of file one
< 7. tape rfm - moves you to the end of file two
< 8. tape rfm - this is not a failure, it's a *feature* :-)
Actually, this moves you beyond the end of the file mark, because the previous
tape rfm leaves it at the file mark.
< 9. tar cv file3
< 10. tape rewind
< 11. tape rfm
< 12. tape rfm
< 13. tape rfm - now you are positioned at the end of the second file.
< 14. tar tvf ( or xvf ) /dev/rct0 ( can you beleive this? I can't )
< 15. THIS WORKS..... ^^^^--- notice *rct0* not nrct0, - ask SCO why!
It doesn't matter which you choose, unless you want to add another file after
this one. The nrct driver means "don't rewind _ON_CLOSE_". Only use the
rct driver if you want the tape rewound after each close.
[minor (probably unwarranted; most are) flame against SCO removed]
You could, of course use "tar rv files files files", and get them added on to
the end of the current archive, so you didn't have to run tar 3 times to get
all the data off of the tape.
--
Steve Watt
...!claris!wattres!steve wattres!steve@claris.com also works
If you torture your data long enough, it'll eventually confess.paul@frcs.UUCP (Paul Nash) (03/20/90)
In article <446@wattres.UUCP>, steve@wattres.UUCP (Steve Watt) writes: > In article <262@netdev.Comsys.COM> root@netdev.Comsys.COM (Alex Huppenthal) writes: > < How can I add to the end of tar archives ? tar cv, tar cv works, but > [minor (probably unwarranted; most are) flame against SCO removed] > > You could, of course use "tar rv files files files", and get them added to If this actually _worked_, the flame would have been unwarranted, BUT SCO Xenix does not allow updating tape archives (or disk file archives!) - only floppy disks can be updated. RTFM :-} The only way to get a single archive in Xenix is to `tar x', add the new stuff, and then `tar c' ... NOT NICE!! -- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- ...!uunet!ddsw1!olsa99!tabbs!frcs!paul paul@frcs.UUCP -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-